With ThinkPads, just buy a few generations behind refurbished, preferably from a nonprofit recycler. They've always been great for Linux. The T series gives you more upgrade options, but the X models run longer on a charge and are small and light . I'm on my second now, having "upgraded" from a T430 to an X250. But I miss the larger screen and so will probably get a T470 or T480 soon.
Running boring plain vanilla Ubuntu LTS with the ("curse you, FreeDesktop.org!") Gnome Shell and a few extensions that probably drive the minimalists on the Gnome Project bonkers (also running a lot of web apps like Gmail and Keep as PWAs). Or at least I hope they do. Mostly program, don't game: I leave that to my kids, both game developers. As a literal greybeard I don't care much if The Year of the Linux Desktop ever comes, because I've been living The Life of the Linux Desktop for over two decades.
Still using docker for workloads at home, but if I was still managing massive numbers of containers at work I'd probably be running podman for anything that didn't justify the cost and complexity of k8s.