Just a few days ago I installed Arch Linux on a ThinkPad P15 Gen 1 with X Server and i3wm for wm, disk encryption, multiple displays and it works very well. Heck, even the touch screen is working OOB without any special configuration. I've always been installing Arch Linux on ThinkPads that came with Windows pre installed. There are minor issues at times with backlight control or sound system which is mostly due to my minimal setup but overall I don't feel that ThinkPads don't play well with Linux.