I guess I've never understood why people think this matters. If they can get away with not having it a level playing field, with no adverse consequences for their markets, what incentive could they possibly have to level it? If there is no market incentive for an action they won't take it, simple as that. People who want to force regulation on them are literally trying to fight against the free market.
I think the problem is those same people turn around and get worked up when Trump puts tariffs up, when the same exact logic applies. Both are rational self-preservation techniques, but China gets a lot more sympathy for some reason with many here.
One reason people may not like the pushback against China (besides the source) is they are personally enriched in the status quo, and fear (correctly or not; time will tell) that a change will affect their enrichment.
It seems obvious, but it's worth repeating, a trade agreement can be a massive net negative for an entire country, but incredibly profitable for a few people.