[0]: https://buffer.com
Still, mine is just a guess.
edit: Come to think of it, didn't FB eventually moved from super open API to.. friend and family model?
Disabling APIs won't win you any friends
[0]: https://buffer.com
Note: They seem to support "Instagram, TikTok, Facebook, Twitter, Pinterest, LinkedIn, and Google Business Profile"
You can't consume or publish to a personal Facebook profile or an individual Instagram account; it's restricted to Facebook Business Pages, Groups, and Instagram Business accounts.
It does compete with the Meta Business Suite, though.
I know I was a heavy user until (uh) 5? years ago when Instagram and Facebook posting was nerfed into uselessness.