They would have the same experience with Modula-2, Object Pascal, Delphi, or even Go's predecessors Oberon-2 and Limbo, with the difference that all of them had better tooling for GUI development 20+ years ago.

Faster compile times, debugger, IDE, code formating on save, proper modules, choice of static or dynamic loading,... all there.

Go ties to Google made it have better fortune in the market than those languages.