I think it also is a generalization which is more about a systemic problem rather than a specific player issue.
To use your example, a minority in the United States who rages that all white people are racist is probably wrong, but someone who says that society as a whole in the United States is racist and disenfranchises minorities is pretty accurate. The data for SES and legal treatment and a few other markers is pretty clear that minorities get the shit end of the stick in the United States, and while a lot of it isn't intentional (for instance a lot of schooling inequalities come from the fact that real estate taxes often fund schools in the area and after WW II GI bills could be applied for to buy new homes, but only by whites and not blacks, so the average value of a random white person's home is higher than the average value of a random black person's home from the houses passed down that were obtained w/ that discrimination, and thus the average public education offered to the average minority is funded less), it's still a true statement.
Similarly, good supports are less noticeable and bad ones are easily noticeable. I've heard a lot of games rave about a good adc who carried them, but only been in a few where the adc raved about the support being awesome and how easy it was to carry when they are so ahead bc the support absolutely crushed in lane. On the other hand, when there is no vision, it is always the support who gets blamed for it, even w/ the advent of upgraded yellow trinkets which let a team drop a bunch of wards even if the support isn't doing a good job (so part of the fault lies w/ the team if there aren't at least 4-6 other wards down and you're complaining the support doesn't have 1 down). It's really noticeable when a support doesn't ward or engages bad, but if an adc could have lived w/ better positioning and didn't it's easy to blame peel or say the enemy had good dive bc positioning is more subtle. Not every adc is a jerk, and if you're a good support they're probably nice bc they are happy to have you. However, if you fill support and aren't that great, it's easy to blame the support rather than other players for the team struggling, bc the game just is set up to make it more obvious when your support is doing bad.
