It is interesting, my EU iPhone can use Chinese eSims unrestricted in Mainland (via trip.com), advertised as HK/Macao/Mainland travel eSims. As other have said, iPhones for the Chinese market can not. So the phone smuggling is still big business. Also, there is a quota on the amount of sims given out each month, but dont er quote me on that (at least that was the case with physical HK/Mainland sims sold in HK Shamshuipo etc).