I don't see an issue with that to be honest.
Say you bought a 5900(non x) for $300(two functional chiplets that have 2 cores disable each), then you would like to upgrade to the 5950X, you can sell the used CPU and put the difference to upgrade to a $700 5950X, but if AMD give you the option to unlock four cores and OC capabilities by downloading a Firmware for $100? How is that not the best way to upgrade?
Or if Intel lets you upgrade from a 12600K to a fully functional 12900K by Firmware alone? That saves a lot of time on physically upgrading your CPU