Infra guys doing DBA is a nightmare in my experience (usually clueless and it gets loved less than more sexy parts of infra). Devs too
Hire a DBA ASAP. They need to reign in also the laziness of all other developers when designing and interacting with the DB. The horrors a dev can create in the DB can take years to undo
I'm a little afraid to say it but LLMs are getting quite good at query optimization. They can also read slow query logs and use extensions like pg_stat_statements
Doesn't necessarily prevent a terrible schema but it's become a lot easier to fix abomination queries at least
As an infra person I couldn't agree more. Get an expert in there. DB's are their own universe of complexity and deserve dedicated attention.