Buy a ThinkPad. Install Ubuntu. Don't think about it again for 6-10 years.
I have a T480/Ubuntu-Gnome at work and a T480/Debian-KDE at home, both work fantastic, however for some reason the Lenovo Universal USB-C docks with 2 1080p external displays connected (1 HDMI and 1 DP) cause a lot of Gnome crashes when docking, and when it happens, I lose external displays and/or the usb keyboard, and have to spend 15 minutes fiddling around deactivating and reactivating in settings, or unplugging t…
Gaming I don't even attempt on Linux, though I've met two or three people now who are convinced you can 100% do it these days with Wine-based platforms and the right drivers.
Docks, in my limited experience, are a shit show on any system. I use Lenovo's thunderbolt dock (the expensive one) with my X1 Carbon Gen 6. It mostly works. I've been having problems with HDMI lately, no idea why.
FWIW, I used to have a super duper high end MacBook from work. It had similar problems. :shrug: