My impression from working on an app with a Postgres cluster of 128-ish instances is that Postgres is excellent when your largest table fits on 1 instance, and

My impression from working on an app with a Postgres cluster of 128-ish instances is that Postgres is excellent when your largest table fits on 1 instance, and kinda lacking when you need >1 instance for your largest table. MySQL has very mature cluster managers like Vitess / Planetscale. Citus for Postgres was bought by Microsoft and doesn’t seem as popular as Vitess.