Comment by dvdkon

The verified bootloader would register the signature of the kernel into the TPM, so a malicious kernel would be noticeable. You could still exploit the kernel, of course.

Even a hacked kernel won't have access to the key material stored inside of the TPM, though, so it wouldn't be able to fake the remote attestation key material used to sign any challenges.

Using TPMs this way requires secure boot which only permits non-exploited, signed kernels to load signed operating system images and signed drivers. Revocation of exploitable software and hardware must be harsh and immediate. That means most dTPMs (which have been proven vulnerable to numerous side-channel attacks) are unusable, as well as some fTPMs from CPUs running old microcode. Several graphics cards cannot be used anymore because their drivers contain unpatched vulnerabilities. Running tools with known-exploitable drivers, such as CPU-Z and some motherboard vendor software, would imply a permanent ban.

This approach can work well for remotely validating the state of devices in a highly secure government programme with strict asset management. For gaming, many hardware and software configurations wouldn't be validatable and you'd lose too much money. Unfortunately, unlike on consoles, hardware and software vendors just don't give a shit about security when there's a risk of mild user inconvenience, so their security features cannot be relied upon.

You can do what some games do and use TPMs as your system's hardware identifier, requiring cheaters to buy whole new CPUs/motherboards every time an account is banned. You can also take into account systems like these but don't rely on them entirely, combining them with kernel-level anticheat like BF6 does (which requires secure boot to be enabled and VBS to be available to launch, though there are already cheaters in that game).