Which defaults? The programming languages I’ve worked with don’t have defaults for everything related to formatting. Editor defaults don’t work, since not everybody uses the same editor. So you have to make a choice somewhere.
A lot of (relatively) recent languages do have defaults. Go and rust both come with an auto formatter out of the box, and defaults that are sane enough to just run with
Ah yeah, in those cases it is possible to just use the defaults.
Come to think of it, I have worked with Deno, which comes with a formatter (and linter and testing library) and I’m a fan. Saves a couple of dependencies, some config files and a bit of mental overhead when creating a new project.