It's important to note that more work is needed to improve the accessibility stack on Linux; if you want to contribute you can read the at-spi2-core developers documentation for an overview of the stack: https://gnome.pages.gitlab.gnome.org/at-spi2-core/devel-docs/index.html
We especially need more documentation on how ATs interpret the accessibility interfaces, and what kind of expectations should be satisfied by toolkits and apps.