Summary: schools and companies sell their old laptops to recyclers, but don't unlock them first. Historically recyclers never needed to coordinate with the previous owners because once they had the hardware they could do anything they needed. With new security chips, however, these locked computers are nearly worthless.

Since these computers are still valuable, I think we probably end up with a new dynamic where contracts are updated so the previous owners get money back for unlocking them first. That maintains their value without opening a path for thieves to unlock and resell stolen macs.