Low hanging fruit, but whatever. It is what it is.
Good luck opening more than like 5 browser windows on those old thinkpads
The refurbished thinkpads you find are usually three years old after the companies who lease them buy new ones for the users.
You can do a lot of things with a three year old thinkpad…
here it’s typically early-to-mid 2010s thinkpads being sold, so you’re probably getting a laptop with horrible performance
4th and 6th gen intel isn’t too bad yet (which would be early 2010s), especially for a Linux desktop/laptop. I wouldn’t go older than that just because 4th and 6th gen is so readily available for so cheap, but they certainly aren’t anywhere near e-waste yet. Mid-2010s would be more like 7th-9th gen Intel which is newer than all but one of the computers in my home.
I literally use a laptop with a mobile i7-6700 as a daily web browsing computer (and I tend to keep over a hundred tabs open) and really don’t feel any slowness. I’ve got a desktop with an i5-4590 running 5 different Minecraft servers (a couple of which have over 300 mods running) plus most of my homelab services as well. They’re not for the graveyard yet!