I've been running a fairly lean install of Debian as my main OS (well, as my ONLY OS, to be honest) since 2014. This year I got a new job that required me to use Mac OS* (Big Sur, 11.3.1). I'm two weeks in, and here's my impression:
Mac OS looks very nice. There's a lot of preloaded stuff that I'll never use, but overall the system feels pretty tidy and consistent. It's sorta irksome that THIS IS THE UI YOU GET. PERIOD. But, hey, that's how you keep things tidy and consistent: you bolt down the furniture and don't allow food or drink on the premises.
There's a lot of stuff that I'll simply have to get accustomed to, like new hotkeys and an overall more pointing-device-dependent way of working and getting around. I'll try not to harp on too much about that because it's a bit silly to say that system B is inferior to system A because they are not identical. It's (mostly) stuff that I'll just get acclimated to.
The user-experience thing that sticks out to me is this: for my usage profile, my wimpy little Debian machine is faster, snappier, more responsive. The Mac is a very fast machine: 6-core i5 @3.3GHz, with 32GB of DDR4 RAM and a Radeon Pro 5300 pushing pixels. My Debian system is a little Intel N5000 machine (quad-core, 1.1GHz) with 4GB of RAM and some onboard Intel graphics. For drawing -- which is the only area in which I NEED a high degree of responsivity -- the Debian machine is more performant. There are milliseconds of lag and dropped events on the Mac, and I find it quite frustrating/unpleasant to use for that purpose. It's not just Photoshop; the latency is high in Sketchbook, Krita, Clip Studio Paint, ...everything I've tried on the machine. Maybe Wacom's Mac drivers are crummy. Maybe one of the cloud services or groupware apps I was required to install is gumming things up. I really don't know, but the bottom-line is that I find my lean Debian machine gives me what I need where I need it. I twitch my wrist, and those pixels go down on the canvas IMMEDIATELY.
Incidentally, this is consistent with my other recent Mac experience. I was given an old 2010 Macbook Pro by a family member. They'd wiped it and had a fresh OS install done at the Apple store before giving it to me. I (of course) installed Debian on a separate partition and have been keeping it around as a dual-boot Mac/Debian system*. When it's booted into Debian, it's a fast machine. When booted into Mac OS, it's kind-of a potato. There's just so much overhead with all those good looks, I guess.
Unfortunately, I can't dual-boot the new iMac. I have some stuff I'm required to run for work that isn't available on GNU/Linux, so it's got to stay Mac OS. For most of the graphics tasks I'm required to do, I'm also tied to Photoshop (we make heavy use of shared library assets/Creative Cloud). However, when it comes to sketching-out new character designs, where I am at liberty to use whatever tools I want, I think I'll just keep doing it on my Debian machine.