In related client API news, Dave Winer has also been hammering on this recently from his perspective working on WordLand and the long history of the MetaWeblog API:

But the web is what matters, not my product or yours. Even if your product is huge, it’s only part of the web. This is how we build, how we get back on track. Somehow we need to get a simple bridge that lets all blog content flow to Mastodon.

Lear year, I really wanted to see Mastodon adopt an open posting API. I even wrote a FEP to fix some limitations in how APIs were too hard-coded to Mastodon’s capabilities. It went nowhere.