people are working with different mental definitions of "accessibility"
one definition might be something like "features that make a platform easier to use and more functional for people with certain disabilities."
sounds like a solid definition, but it leaves a lot of questions open: what counts as disability? what's the difference between an obstacle and an inconvenience? is there one?
i think these things are a spectrum. there's not necessarily a bright line between problems that make a platform worse to use, versus problems that keep someone off a platform. increasing friction is going to make more and more people have issues, but the specific place they draw the line and decide it's not worth dealing with is gonna vary.
i also think it's not that clear-cut who "counts" as disabled, and in some cases the platform can't necessarily do anything to help them. if someone is too anxious to post, is that a disability? what if they're anxious because someone keeps leaving comments that upset them, but this user has a moral objection to blocking people? in that case, the feature to solve their issue is there, but does thar matter if they're not willing to use it? is that an accessibility issue or not?
is the accessibility of a platform solely a function of what features it has? or does it emerge from the interface or platform and user? is there a single objective level of accessibility that a site has, or does it make more sense to look at this through the lens of many individuals and how accessible it is to them?
i don't have answers. i just think this is a complicated and nuanced topic that goes way beyond a dichotomy of "this site is good and accessible" versus "this site is bad and doesn't care about accessibility"