This is so amazing. If I had a 10th or 11th gen i7 laptop, no way I'd rush out and buy a new laptop for two or three grand. But a new mainboard for $600? Yeah, that's an annual upgrade train I can get on!

Given that one of their stated targets is sustainability, this sounds like Jevons paradox [0]. This might be averted a bit, though, if you reuse the old mainboards for things like a homeserver.

[0] https://en.wikipedia.org/wiki/Jevons_paradox

You can also sell them to people who don't need the latest and greatest and are happy to buy a still more than adequate used machine part

They'd still need a framework chassis, so this market is probably a tad smaller (either they are late upgraders or something broke). But yes, this works, too.