IIRC my issue with MacPorts was that it insisted on recompiling the world from its ecosystem as dependencies because it kept everything super-stable, whereas brew would attempt to use system ones if they were viable. It was more or less FreeBSD Ports vs. Debian apt-get as the model at that point, and MacPorts was (predictably) FreeBSD-like.

Over time I'm not sure brew is any better now, though. I have unlinked versions of gcc, python, etc., etc. under /usr/local that are there just to handle brew packages that listed them as pinned dependencies. It's nice that brew doesn't expose them to CLI unless I want it to do so, but it's not less complex.

Assuming MacPorts has a good "bottle" type concept of precompiled packages now too (haven't looked for years) it's probably about the same as brew now, just more stable. If they still compile from source every time a la BSD, that would be my main sticking point.