You really point out that you’re going to require a dedicated team to manage all the things you’ll need. I you’re not at this scale there will be a lot of overhead to manage for the dev teams.

I’m in a team like this, supporting a bunch of developers - we build a CLI, an API (in our domain! It’s just another domain with the devs as consumers) and juggle approx. 16 different tools (monitoring, metrics, tracing, service discovery, etc etc).

Doing it through custom tooling that enforces conventions is, IMHO, the way to do it successfully.