I believe that's coming from homebrew itself, which is pretty aggressive about updating everything. The homebrew formula contains no reference to xcode version, for example: https://github.com/Homebrew/homebrew-core/blob/master/Formul...

Good call. Thanks!

So download a binary instead of building it from source?

Came here to whine, got a what seems in retrospect to be a perfectly obvious and simple _solution_. Thank you!