In my limited experience (no longer using macOS after ~6 years on the platform), homebrew upgrades was broken more often than upgrades provided by GUI applications. I specifically remember a particular postgres upgrade via homebrew went wrong and I had to basically erase all traces of postgres before re-installing again in order to get it to work. On the other hand, I can remember zero times a GUI upgrade went wrong.
I have been using it for 2 yesrs now. Did not have any problem upgrading changing the version etc. Homebrew breaks things often. The App just works I never have to care about it.
I've had the exact opposite experience with Homebrew vs GUI installers. Postgres.app has never had any issues, while Homebrew postgres breaks every time I run `brew update`, because of the way homebrew handles icu4 library dependencies.