I’m a DBRE, which means it’s somehow always my fault until proven otherwise. And even then, it’s usually on me to work around the insane schema dreamt up by the devs.

Multi-tenant DBs can work fine as long as every app has its own users, everyone goes through a connection pooler / load balancer, and every user has rate limits. You want to write shitty queries that time out? Not my problem. Your GraphQL BFF bullshit is trying to make 10,000 QPS? Nope, sorry, try again later.

EDIT: I say “not my problem,” but as mentioned, it inevitably becomes my problem. Because “just unblock them so the site is functional” is far more attractive to the C-Suite than “slow down velocity to ensure the dev teams are doing things right.”