I just did a quick check: a 2022 Macbook pro M1 with 1tb and 16gb ram goes for 1119 euros on eBay. A new M5 mbp with the same ram and disk is 1899 euros, so 709 difference. And you get a whole new machine not just a cpu upgrade.
On the other hand, if something fails out of the warranty, this is where you win with Framework.