Personally I think the challenges with this approach (having literally used a Go shared library + native UI myself): 1. The web still exists. You can't practically use a Go shared library on the web. And you probably don't want your shared library written in JS. 2. In my experience, most of the coordination is about the UI, not the underlying implementation. So the human cost isn't reduced much with shared libraries. 3. At a big company, "feature teams" can't easily ship native desktop UI because feature team eng only knows web...

I do think this approach is super viable with a product development approach that is more waterfall, however. Where a team owns the platform and it's design.