Yeah, currently I have a 3B, 2B and an original wifi-free zero in a drawer.

The 3B was my Octoprint server for the longest time while I was testing the 4B for a product, but for reasons I don't really understand, the 3B isn't quite punchy enough for Klipper, when it fully should be; it drops connections to the printer. I think any of them may continue to have some uses but perhaps not till I move to a new place.

Haven't gone for a 5B or Zero 2W yet, don't really need to. Rather more interested in what happens with the Picos these days.