If your computer is backdoored, then a HSM does not protect effectively against that attacker. At some point the computer will see the data, at which point it can be extracted. The key is not important to the attacker which can read the unencrypted data.

A HSM does make attacks more difficult, and that is important. On the other hand, computers without backdoors would be _the_ significant step, though, to change the game.

I fundamentally dislike Intel and AMD for their stance on this. And I'm not alone.