Comment by SwiftyBug
One thing I couldn't find in your post was the reason behind choosing the ThinkBook. I'm about to make the exact same switch you did (thanks for bringing up Omarchy, I hadn't heard of it before!). I'm considering a ThinkPad P14s. What made you decide on the ThinkBook?
My requirements were: affordable, as i didn't know if I stick to it, 32 GB of RAM, 14'' form factor and good keyboard. AMD for good Linux support. This ThinkBooks popped up, and I liked the look and just tried it. The matt screen was a bonus.