Yes, sure. But the difficulty about monitoring is not the hosting per-se, but hosting in different datacenters throughout the world abd keeping all these services up.
My monitoring should not show "just down" if users from location A can't reach it but everyone else can.
Yes, or a new company could post on Reddit, "would anyone like this service?" and spin up a replacement. Probably not worth it in this instance, but I imagine a lot of people sleep better at night knowing that Postgres is available to self-host, or from a variety of cloud providers.
It's worth coming up with a stronger public-facing answer
We went through this last year, I think we have a public one, a private one, + our actual more 'serious' telemetry (opentelemetry, ...). For the status pages, I think one we don't pay for, and the other is like $20/yr.
Only software devs care about this. Your competitors make millions of $ annually, without being open-source.