I always assumed this is because Linux package managers such as apt and yum are first-class citizens on the platform, while Homebrew is a bit of a de-facto solution on macOS.
No, macports is non-native as well and is an excellent, stable alternative, although Homebrew has slightly better coverage. Homebrew's main issue is that it was written from scratch, ignoring lessons from 30+ years of package management experience, and there's no obvious benefit that doing so has brought. Compared to macports, which is based on freebsd ports, Homebrew is brittle and normal operations frequently result in an inconsistent state.
In my experience, unless your needs are extremely basic, sooner or later you'll run into an issue where the solution is basically to commit nuclear warfare on your filesystem and start over again. Also, expect to rely on random blog posts and stack overflow as the de facto user's guide (which maybe is just the state of the world for everything now.)
As to Homebrew, I don't understand why it complains if I use sudo to do an install but then also complains if I'm not running as an admin account! If there's a reason for this splitting of hairs, I don't know what it is.
In my experience, unless your needs are extremely basic, sooner or later you'll run into an issue where the solution is basically to commit nuclear warfare on your filesystem and start over again. Also, expect to rely on random blog posts and stack overflow as the de facto user's guide (which maybe is just the state of the world for everything now.)