us companies are subject to lawsuits from us citizens and government

In theory. On the ground - they just provide a market hall, with no liability and fitness of purpose implied.

The same unbranded, zero QA, zero accountability products direct from China being sold on Amazon are also a problem. The only difference with Amazon that puts them like a single rung above Temu and Shien is that they also sell proper branded, non-counterfeit items (though my understanding for a while has been that counterfeits do end up getting mixed in with legit items).