If Go 2 won't break Go 1 programs, shouldn't it be Go 1? I get not using semantic versioning for end user packages like a web browser, but for backend systems

If Go 2 won't break Go 1 programs, shouldn't it be Go 1? I get not using semantic versioning for end user packages like a web browser, but for backend systems and APIs, it still makes sense. I don't see why go didn't use full semantic versioning (x.y.z) where any update that didn't break anything moved Z, new APIs or minor changes to behavior/compile such as in the article move Y, and large changes to the core language or core libraries moves X. By semantic versioning, they aren't moving off "Go 1" any time soon, no matter what it's called.