[michaelt]

> In my mind that's the main thing a TPM is really useful for.

Unfortunately, it's not much good for that either.

A yubikey has a button to confirm the user's presence - so even if a remote attacker has completely compromised the machine, because they can't press the button, they can't get anything out of the key.

The TPM has no button, so it has to rely on the OS to keep your pin safe from keyloggers. If your OS is that trustworthy, you might as well just store your secrets in the OS keyring.

The TPM is also about 50x more complicated than a yubikey, to support things like multi-user systems. This means there's a much bigger attack surface.

[lxgr]

The button of a Yubikey doesn't add as much security as you might think: Since you don't know what you are actually confirming (due to the lack of a display), what prevents an attacker with control over your OS to just wait until you want to confirm something legitimate and then front-run that request?