Sure. Or the supply chain attacker (who is perhaps a state-level actor if you want to think really spicy thoughts) selling you a device on Amazon you think is secure, that they messed with when it passed through their hands on its way to you.
The evil of the type of attack here is that the firmware with an exploit would be properly signed, so the firmware update systems on the chip would install it (and encrypt it with the PUF-based key) unless you have anti-rollback.
Of course, with a skilled enough attacker, anything is possible.