The TPM is on the motherboard as far as i know? I remember the mobos were specifying if they run windows 11 in descriptions when I ordered.

Besides I bought AMD. Needed the thing for parallel builds and I was getting more cores for my money. Plus actually usable integrated graphics. Plus less power consumption.

Many custom build PCs had the fTPM disabled by default in the bios. It was buggy and caused performance issues on AMD systems at the time and since few people buying their own motherboards were using it, it was a pretty obvious fix for the motherboard makers.