I did this. Was a ThinkPad Linuxer for years and now I just use an M1 for sysadmin/programming/web/vids. Quite happy to just use Linux on my servers these days. MacOS does the job nicely on laptop. I suppose it depends on how FOSS you want to be.
I recently bought a MacBook Air M1 and I came at it from a classic “ThinkPad with Fedora on it” Linux nerd perspective. I got given a Mac at work a couple of years ago, and I warmed to it. I agree that Macs are great tools for DevOps work. I used to think they were just for posers but I’ve been converted.
Just use a $5 USB-C to 3.5mm DAC?
I home brew installed most stuff, yeah. I’m lucky in that I don’t need a whole lot of stuff installed. Just a couple of JetBrains IDE’s, a couple of browsers, iTerm2 and a handful of popular CLI utilities.