“They are basic small form factor Dell PCs.”
I bought one used on ebay last week. OptiPlex desktop SFF 5000 / i5-12500 / 32gb ram / The 32gb was crucial to me buying it. This way I do not have to buy any more ddr4.
But 16gb is good enough for most people. There are many Dell business class computers (OptiPlex) and desktop and (Latitude, Precision) laptops. They all can run Mint Linux if you prefer. Dell has been selling Linux computers for years. I turned one 150$ Latitude 5520 / 11th gen Intel/ 8gb RAM into a Chromebook.
I’m looking at getting a eBay refurb higher end laptop to make my Linux daily driver.
The windows boxes have a few things that I need from time to time and emergency spares in case the spouse’s unit fails.
I’ve been sending 4 and 8 gb sticks to electronic scrap at the office.