You can force everyone on a project to use a formatter just as easily in any of those languages as you can in Go, with a few lines in your CI job definitions. Whether they're third-party or not is irrelevant.

It's not irrelevant, it's the entire point. The whole Go ecosystem uses a single formatter. There's no need to force anyone, everyone just uses gofmt. You will not be able to replicate that level of ubiquity easily at all.

Not really true because you have both gofmt and gofumpt, and gofmt can be run with -s or not, and also lots of projects are using separate linters to enforce maximum line length.

But true enough.

Not true. Because after running go fmt and pushing our CI fails because of other stylistic concerns that are checked by another tool.

You can only force everyone on a project to use a formatter if you are the one who has the authority to decree what will be done on the team. OTOH, if you are but a team member and you join a team where the manager does not think common formatting is important, then you get f*ck all.

So being built-in, idiomatic and expected cannot be over-appreciated.