I'm thankful to Supabase for their efforts, but I'm not sure I'd pick pgAdmin and migra as examples of "really effective" collaboration with other teams: as far as I know, pgAdmin's CLI feature wasn't merged upstream and sits in an outdated Supabase fork of pgAdmin which doesn't fully support Postgres 15, and migra (which has been abandoned for a while) was just used as-is.
(but I agree with the sentiment: we can always find ways to be more collaborative)
we talked in the past about using their library to extend some of Dan Lynch's work (https://github.com/pyramation/postgres-ast-deparser) to create a sort of "postgres package registry" with dynamic DDL introspection. No progress on that one yet, but I'm hopeful that we'll find the bandwidth for it one day.