The reasons I buy second hand thinkpads, is because I have expectations about the keyboard, and they're usually met.

I have expectations about the screen not being silly DPI and 'reasonable', and that's usually met too.

Bluetooth etc. works just fine.

Finally I have expectations on the fans not being like a total joke on most windows laptops... and that's usually fine too.

For the rest I want compatibility; lack of 'FML quirks'.

If only they could fix the absolute turd of audio quality in thinkpads, I think we'd be on par with Apple from my perspective. Although I've loved ARM processors lately and would always prefer a portable ARM machine than Intel.

Choosing thinkpads is really mostly about choosing the boring option, with the least amount of surprises, the dad option of laptops in a sea of disappointments.