Oh, net/http recovers from a panic inside a handler and sends error 500. I don't know if that was always the default. Where I worked before, our own Go servers didn't recover, and it did cause outages.
This is kinda bad practice. Go and Rust panics are similar, they aren't exceptions that you can safely recover from. Say there's a panic in the middle of modifying some global state like a database connection. Hence complaints about the net/http recover like https://github.com/golang/go/issues/25245 . But I guess they decided it's worse to let servers crash from trivial mistakes.