> what you're asking is "why don't Apple and Microsoft make it easier for developers to make software developed on Apple platforms better on Microsoft or vice versa"
No, what I'm asking is why the responsibility is always put on GUI toolkit developers. If a good cross platform a11y API is possible, the moral obligation is on the OS vendors to create it and support it. If it's not possible, then why do we treat GUI toolkit devs not only as if it is, but it's somehow their job to re-implement it for every GUI library?
The point I'm making is that its OS vendors job to develop one platform, not software that works on multiple. It seems like you misunderstand that. They don't have a moral obligation to develop APIs that work for other platforms - that's absurd. That's not even what POSIX is, and like I said, POSIX doesn't even cut it for these applications.
The obligation is in the developers making cross platform layers, like GUI toolkits. There's no obligation for MS and Apple to agree on an API, but there is an obligation for the software claiming to target both to support both APIs. That's the very nature of making something cross platform!
No, what I'm asking is why the responsibility is always put on GUI toolkit developers. If a good cross platform a11y API is possible, the moral obligation is on the OS vendors to create it and support it. If it's not possible, then why do we treat GUI toolkit devs not only as if it is, but it's somehow their job to re-implement it for every GUI library?