Maybe it's just different strokes for different folks, but I'd much rather just clone my dotfiles and have a Linux workspace up and running in ~10 minutes tops. Moving my workflow over to MacOS feels like trying to board a plane while it's taking off, and it doesn't bode well for my productivity when I can't rely on my tools even showing up in the first place.
If you really want an apt-get (never used pacman) kind of everything-repository experience, though, you're going to be disappointed on any system that doesn't prioritize a centralized repository of software. In practice, this eliminates a commercial OS, and probably commercial software, since there's no effective way to get a central repository. The App Store is the closest, but then you get people complaining you're the gatekeeper, or you get a free-for-all like Google Play. I think Linux manages only because the number of people that use it are small enough that bad actors go elsewhere.
I'm asking because I'm assuming your real issues are with your stated reasons, since MacPorts is a "proper package manager" (being ported from one of the BSDs) and if you don't like that one, Brew is certainly popular. And I've never directly benefited from Linux being an "open operating system", since I don't write code that interacts with anything lower-level than the C API, but macOS' Darwin kernel and many of the binaries are open source.
I'm kind of old-school (my intro to Unix was a DECStation), and I find macOS to be plenty Unixy. If I'm not using Xcode I'm using Emacs (in VI mode). I've never said "I wish I had <Linux feature>"; actually, it's been rather nice that my Wifi doesn't break, I don't have to deal with PulseAudio, it goes to sleep--and wakes up!--when I open and close the lid, the UI is unified, networking is easy to use, etc. However, if you run the Linux GUI applications on macOS it's a klunky experience, so you benefit from finding native applications. Also, Docker wasn't very pleasant, but that might have just been Docker; fortunately I've only had to use it for one project.
As someone who loves the macOS + Unix experience, I'm just curious what workflow it doesn't work well with.