Global users can unlock Xiaomi phones, but have to jump through more hoops and deal with restrictions. For example, there now seems to be a daily limit on how many devices their server accepts to unlock. Took me three tries to be successful in the “first come, first serve” line.
Afaik, Chinese users are now dependent on paid services to unlock their phonew for them. How they get around the official restrictions? I don’t know.
I just upgraded to a 5700X3D and hope to skip AM5 altogether.