Early Javascript and HTTP based APIs killed a lot of it. People generally did not want to put a ton of serialization code into their websites, just to call some API. Building XML and JSON APIs into the browsers was much more attractive.

That's started going the other direction, with people are more willing to do things like generate code for GraphQL, now that code size is less of an issue.

Besides that, a lot of these protocols come with other baggage due to their legacy. Try reading the COM documentation relating to threading: https://learn.microsoft.com/en-us/windows/win32/com/in-proce...