Just because there's a "rule" that exists somewhere in the abstract, that doesn't mean folks should assail people for innocent mistakes. It's also not a rule of this community. It's not a rule of the instance this community is a part of. It's most definitely not a rule of "the platform."

In fact, these the W3C (the body most people are seemingly citing as a source for rules) isn't even calling their "rules", rules. They call them "guidelines" https://www.w3.org/WAI/standards-guidelines/.

Ya, I'm colorblind, but you're probably not and you probably didn't think about it. You're just some random person on the internet, you've probably got plenty of other things to worry about than hunting down the latest WC3 publication on accessibility.

To be clear, I do let folks know if there's a chart I'm interested in reading that I can't read, try to give feedback about colorblind relevant stuff, etc. (literally last night I was on the Deadlock forums giving Valve accessibility feedback). I just do it in a "matter of the fact" fashion and try to explain what I'm struggling with rather than with an attitude and command that they change something without any context.