That was the Nixon/Kissinger theory of the 1960s/70s. It was used to cut China all sort of political and economic slack. It was proven wrong by the 1989 Tiananmen Square Massacre.
Was it, though? China circa 1960s/70s was a totalitarian dictatorship where Tiananmen square was an impossibility simply because any dissent would be crushed long before it would get to mass protest stage, and the yearly number of victims was far greater, too. Compared to China after Tiananmen, the latter is far more liberal. It's even more liberal today.
If you want a better China then the US should treat China as China treats the US. Have reciprocal economic and trade policies, punitive measures for egregious behavior, ... No more cutting them slack hoping they will moderate over time, no more treating them like they are an impoverished developing nation,
I did not suggest doing such a thing. The best thing you can do is just trade (and yes, this doesn't preclude e.g. tariffs to even out the price of labor differences, environmental concerns etc).