Package users should not have to run "go generate". It's mainly for package writers to generate code and then distribute it.
With other languages, you might do code generation through powerful macros (e.g. as rust has) or some other tooling which is not literally just "run a program in the user's path".
I'm not judging the existence of `go generate` or it's merits relative to some other environments. Except makefiles. Makefiles are worse.