Real but temporary security -> This 2048 bit key you generated will be commercial grade protection until at least 2030. Sometime after that computers will be strong enough to brute force it. Do not store anything with this key that will still be highly sensitive in 7 years. It's possible the underlying algorithm is cracked, or a leap in quantum computers happen that will make the key obsolete sooner.
Security theater -> All software running on this chip must be signed with our master key. Please trust all software we sign with this key, and no malicious party will have access to it. You are not allowed to run arbitrary software on your hardware because it is not signed with our key.
In the first case, the security is real. You own the lock, you own the key, and you control the entire security process. In the second case, you neither own the lock, the key, and basically have limited access to your own hardware.