Homebrew links everything by default (at least that's how it was), so you ended up with all kind of extra junk files all over the place you never needed that comes with some packages... all cluttering up things in the /usr/local main directories and the PATH.

Homebrew additionally also had bunch of other directories, a huge git checkout, etc. then add the weird permission restrictions/ limitations on top of it… many packages then stopped supporting the customisation options at some point, so you were forced to rebuild half of them yourself anyway, if you needed the respective options. Now you had even more mess in /usr/local. :-)

It may work for some, but it wasn't for me anymore (and I used Homebrew for many years before that.)