Is there some documentation about general MediaWiki's compliance with Web Content Accessibility Guidelines 2.0 or 2.1? The pages Accessibility and Accessibility and usability cleanup are a starting point. Still, they suggest there is no real drive toward accessibility, not to speak of a compliance overview, etc.
Topic on Project:Support desk/Flow
WCAG are guidelines, and MediaWiki follows most of them to varying degrees in various of its components. We do however not promise compliance (not that it is a legal framework to comply with), and the MW framework as a whole is not regularly tested by a recognized standards body to certify (at the cost of a hefty fee) how much it is or is not 'compliant'.. It also highly depends on what/which functionality you release to which size of audience and if the content authors are the kind of people that mark up their emails with skittle colors.
Thank you for your insight on accessibility with MediaWiki.
Yeah, most of the issues will probably come from users of MediaWiki instances who are unaware of how to create compliant content. I cannot blame them. This is why I asked about plain MediaWiki without user-generated content.
As I learned yesterday while browsing, there are many accessibility testers around. So, I did random tests on some MediaWiki instances, and the results were not bad. Moreover, they provided starting points on how to improve.
If I grokked correctly, e.g., the European Accessibility Act (EAA) should become national law requiring people to provide accessible websites by the end of June 2025. I guess things will get interesting in the first half of next year.