What does "systemic racism" really mean - Part 3

In Part 1 and Part 2 of this multi-part post, I kind of set the scene with a look at some recent interviews and press coverage. But none of that has helped me to understand what "systemic racism" actually means (only that it may not be as simple and straightforward as many people think).
So, a dictionary definition. Well, there isn't really one, "systemic racism" being a phrase and not a word. Merriam-Webster Dictionary defines "racism" as:

1: a belief that race is the primary determinant of human traits and capacities and that racial differences produce an inherent superiority of a particular race.
2a: a doctrine or political program based on the assumption of racism and designed to execute its principles.
2b: a political or social system founded on racism.
3: racial prejudice or discrimination.

A Missouri woman was recently surprised to learn that her request for Merriam Webster to update their definition had been accepted. She wanted the dictionary definition to reflect the existence of "the systemic and institutional racism that, among other things, perpetuates police violence and over-incarceration in Black and other racialized communities".
So, the official definition of "racism" is changing even as we speak. But it still doesn't help us to understand "systemic racism", which is the specific phrase that is currently under debate.
Wikipedia, then? Interestingly, Wikipedia doesn't have a specific entry for "systemic racism"; it just automatically redirects to "institutional racism", which it says is synonymous (although I think some people may dispute that). The page does say "This page has multiple issues. Please help improve it", and its main definition is "a form of racism expressed in the practice of social and political institutions", which is not particularly helpful. But it does go on to identify what I think is probably the key characteristic of  institutional/systemic racism, that "while individual racism is often identifiable because of its overt nature, institutional racism is less perceptible because of its less overt, far more subtle nature", and that it "originates in the operation of established and respected forces in the society, and thus receives far less condemmation" (the latter actually comes from Stokely Carmichael and Charles V. Hamilton's 1967 book Black Power: The Politics of Liberation).
For me, one of the best attempts to pin down the intrinsic nature of system racism comes from the Alberta Civil Liberties Research Centre, which says that, "Systemic racism includes the policies and practices entrenched in established institutions, which results in the exclusion or promotion of designated groups", and that, "it differs from overt discrimination in that no individual intent is necessary". ACLRC goes on to say that systemic racism manifests in two main ways, institutional racism ("racial discrimination that derives from individuals carrying out the dictates of others who are prejudiced or of a prejudiced society") and structural racism ("inequalities rooted in the system-wide operation of a society that excludes substantial numbers of members of particular groups from participation in major social institutions"). It goes on to list examples of systemic racism in certain old laws of Canada (since repealed), in education curricula established mainly for the majority white middle classes, business hiring and advancement practices, and access to sports and recreation.
The American organization Race Forward, on the other hand, takes a less academic approach and chooses to illustrate the various effects of systemic racism, rather than trying to define it, which it illustrates with a series of short videos on the wealth gap, employment, housing discrimination, government surveillance, incarceration, drug arrests, immigration policy, and infant mortality. This is a good way of showing the results of racism, but not much help in identifying the difference between the racism of institutions themselves and the actions and influences of "a few bad eggs" within a variety of organizations and institutions.
The idea of racism as a result of "a few bad eggs" is usually portrayed as a denial or repudiation of systemic racism. However, by denying that racism is perpetrated by individuals, is the implication is that EVERYONE (or, presumably, all white people?) are actively engaged in racist acts? Is this part of the definition of systemic racism? Is there the possibility of "a lot of bad eggs" rather than "a few bad eggs", but still not absolutely everyone? If so, is that still systemic racism, or just a lot of individual racism?
And the idea that systemic racism means that the rules and systems of our institutions are deliberately framed so as to ensure that discrimination and racism occurs (such as in apartheid-era South Africa or segregation-era America) is also presumably not part of the modern definition of "systemic racism". If that were the case, there would presumably be absolutely NO possibility of a black man becoming US President or Commissioner of the Toronto police or President of the Inernational Criminal Court, or of brown men becoming CEO of huge companies like Google, Microsoft and IBM, etc, etc. Or is just the fact that such people have to try harder, and overcome more obstacles, than white people (in which case you get into some rather tricky value judgements and non-measurable factors) sufficient to qualify as systemic racism?
And here's another, more recent, situation to consider: a Mi'kmaq man is killed by New Brunswick police. How do we know that a white guy acting in the same way in the same circumstances would not also have been shot? Is this just the police being trigger-happy and excessively violent and not knowing how to de-escalate a tense situation, or is it the result of racist attitudes and practices? Because these are two quite different things. In fact, can any one individual event, taken on its own, be put down to racism? I understand that several individual events taken together comprise a trend, which is what we are seeing here, and a trend CAN be evidence of underlying systemic problems. But an individual event?
I'm just thinking aloud here. And I repeat that I am not saying that racism does not exist, or that systemic racism does not exist, and I am not even trying to downplay a major problem (in policing and elsewhere), but just trying to understand what it actually means, and how it differs from general, garden-variety racism. In a heated atmosphere like at present, it does get a bit fraught and complicated, and we need to keep our thinking straight. And this is not just semantics for semantics' sake: if people are being asked to admit and acknowledge something, they need to be very clear on exactly what they are being asked to admit and acknowledge.
I think I'm a bit closer to understanding systemic racism  now, but still to say that it's a simple matter, and that semantics should not be used as an excuse for not acknowledging the existence of a perceived problem is at best disingenuous. As I used to get told at school, "first, define your terms". And preferably define them in a way that everyone understands and can agree on.
I think what most people mean by "systemic racism" is not that racism is baked into the actual rules and procedures of the systems of our institutions (which, I must confess, is what I used to think it meant), but that racism is pervasive and widespread IN SPITE OF the system's rules, and that there are insufficient checks and balances built into our systems to root out individual racism where it exists.
In which case would we not be better off calling it "pervasive racism" or "widespread racism"or something? I don't think that such terms mininize or gloss over the problem, or at least no more than calling it "systemic". And it may help people to better understand what we are all talking about.