I built two Ryzen systems over the past couple of weeks.
I ran into an issue in Windows 11 where everything would work, but in security processor details, reports "Attestation not supported". This is on both new builds: (1) Ryzen 3700x, Gigabyte x570 Aorus Elite motherboard; and (2) Ryzen 5800xt, MSI B550-A Pro motherboard.
They have latest bios, fresh win11 installs, TPM enabled and reporting OK in bios, TPM cleared in both bios and Win 11. I spent A LOT of time debugging this before seeing on the net lots of people reporting the same "attestation not supported" for various Ryzen processors.
It doesn't affect my use of Windows 11 pro, including my use of Bitlocker. But, attestation should work and might be important for some corporate installs who use software that uses the attestation.
Although I don't see any official replies from AMD, supposition is that there is a TPM bug in a lot of Ryzen models, but that it will get fixed in future bios patches.
This is not the "stuttering" bug reported by Ryzen users a while back, which I think is mostly fixed in recent bios versions. It is a different issue.