> I think it stems from the unprecedented success of such zealots in the 1980s,
I would challenge this belief, that the success of Linux, or the Web technologies (TCP, HTTP, HTML, etc.) were primarily the result of the zealots from the 80s. I would challenge the belief that protocols for Twitter-like communication fall into the same category as things like POSIX, TCP/IP, HTTP, HTML, etc.
> That's largely been the result of people arguing passionately on the internet to advocate for that level of openness, collab & interop.
My own opinion is the key to success was a large number of people writing useful code and an even larger number of people using that code.
One example that comes to mind is how HTML was spun out from w3c into WhatWG. Controversial at the time to say the least but IMO necessary to get away from the bickering of semantic web folks who were grinding the progress to a halt. HTML 5 won the day over XHTML (actually to my disappointment). The reason wasn't the impassioned arguments of the semantic web zealots, it was the working implementations delivered by the WhatWG members to serve the literal millions of people using their applications. Another example is the success of Linux over Hurd - the latter being a technology initially supported by the most vocal and ideological of all the zealots.
It is a simple fact that if AT garners sufficiently useful implementations and those implementations garner sufficient numbers of users - all of the impassioned arguments against it will have been for naught. So those arguing should probably stop so that they can focus on implementing ActivityPub (or whatever they think is best) and attracting users. I guarantee you that if ActivityPub attracts millions of users then Bluesky will suddenly see the light. They will change course just like every big tech company did when Linux became successful.
It is also why I think all of the hot-air on RSS and Atom was literally wasted. As technologies both have thus-far failed to attract enough users to make it worth it. I would bet that the same will be true of both AT and ActivityPub. Unless someone develops an application that uses one or the other and it manages to attract as many users as Twitter then people are just wasting time for nothing.