This was the idea of ActivityPub.
You have a Client-to-Server and a Server-to-Server portion.
Different diverse Clients can speak to your 1 server!
It would be wonderful.
See the specifications
But unfortunately mastodon does not support the Client-to-Server part and so they have their own “API” for the server.
And so, while upcoming projects will support it, the situation is as bad as it is …
Server run by the main developers of the project It is not focused on any particular niche interest - everyone is welcome as long as you follow our code of conduct!