I own T14s Gen4 Intel and Linux support is perfect, even fingerprint reader works. Zero complaints. I'm mostly using it in clamshell mode connected via USB-C to display with backwards charging, it all just works! I'm also using secureboot with my keys, I cleared all MS keys and it didn't brick the laptop.

My only grievance is a bit buggy firmware. When I turn laptop on or reboot, speakers will randomly be muted (not a problem after OS boots, but for example in UEFI it'll either beep or not beep and that's random). UEFI interface was a bit buggy regarding mouse control, for example I've used to touch and drag things in boot order, but it didn't work and I have to actually press touchbar button down and keeping it like that move cursor. But touch drag works in other places. Not a big issue bit the first time I encountered it, I spent good few minutes trying to make sense of it, as I thought it just does not allow me to reorder boot entries or something like that. But these are small issues and once you've installed OS, you never deal with that.

Oh, and another complaint is that their BIOS update procedure is super weird. I have to find computer with Windows, download some exe, unpack things, find some BAT file and write to USB drive things, then boot from it. Theoretically they publish stuff to fwupd but I don't like this service. My best BIOS update experience was on Asus PC. I just put some bin file onto FAT32 USB drive, entered UEFI configuration, chose "update", selected that file and that's about it. Super easy, every manufacturer must implement this workflow.

Anyway I'm satistfied owner and my next laptop will likely be Thinkpad. Mostly because its stellar Linux support, but also because I didn't have any major issues with my current laptop.

What’s wrong with fwupd? I’ll admit that that the CLI is not exactly awesome, but it seems like a fairly clean implementation of the actual UEFI spec for updates.