So use a card that lets you create virtual card numbers, and use that for your visit, and cancel that virtual number when you get home.
Do retailers in China no longer take cash, is electronic payment the only way? If so I assume foreigners have been using foreign credit cards directly rather than through Alipay etc.? Or do a lot of retailers accept ONLY the home grown payment solutions? I agree that's a problem for people visiting China, but foreign tourism is hardly a big portion of their economy so they probably don't care too much.
I don't remember the exact figure but I read recently that something like 93 or 97% of China's tourism business was domestic, or from other Chinese speaking places like Hong Kong. They aren't gonna be too worried about supporting US or EU tourism, especially with all the rhetoric between the countries probably encouraging most western tourists to go somewhere else.