Keeping the DB local cuts the worst latency spikes, but then you trade away the whole pitch of ephemeral compute and just-in-time scaling, so you end up glued to old-school infra patterns in disguise, plus node affinity and warm-cache babysitting that look a lot like the stuff SQLite was supposed to let you dodge. Add a few readers on volatile nodes and it get ugly fast.

Couldn't have said it better myself.