> I'm assuming there's no real central registry ala pypi/maven/npm?

that's exactly right, unfortunately. it's a bit of the wild-west the it comes to plugins/VSTs in terms of distribution.

and I agree, this feels like the sort of thing that should be pretty solvable, but I think there's a lot of hidden complexity in this problem space. Solving the "version control" aspect of this feels like it should be rather straightforward for a single user, involving multiple users with different Ableton Live versions, different plugins/VSTs (and different versions within those) is where things would undoubtedly get messy.

I do think there is a niche market for this sort of thing, however.