Switched to MacPorts on an older machine which Homebrew dropped support for (and deleted all prebuilt binaries)
While neither is great as a package manager, especiall with their dependency resolution, here are a few pros&cons:
Apps: ++ Brew has a much more up-to-date collection, also more non-source binaries.
App customization:
+ Port, Brew dropped support for custom install flags a while ago
+ Brew you can setup autoupdate for your personal customizations with github actions since the main repo is using them, Ports does it manually, so you can't copy&paste their action for your use
(+ Brew allows you to install Mac .app bundles in a custom folder)
Security: + Ports has a slightly better security model (folder persmissions are better though I think it only matters for multi-user machines, so mostly no relevant; it also does some sandboxing on install via a specially created user), the downside is annoying sudo, but you can remove the need for sudo for some less sensitive ops like update/uninstall to cut down on the annoyance
Space: + Brew. Both waste it with their poor package repository architecture, but with Brew you can at least delete the repo after the first install and use their API to download updates. With Ports you can't do that, moreover it duplicates its registry (one for sync, uncompressed, another for local use)
Docs: + Brew, also random Google/SO answers are less likely to be outdated
UI: + Brew. Has more info (like size), better formatted