Most of what you wrote is blatantly false, though in your case if you're a US citizen then it can be chalked up to unintentional ignorance (since you did not need to go through the regulatory hurdles a non-US citizen would) . You can open and run a 100% foreign owned business in China just like in the US, and you can buy a Chinese company just as easily as you can buy a US company (going through the same regulatory hurdles and mechanisms in both countries). Both countries heavily scrutinize foreign ownership of sensitive industries, but are more lax for nonsensitive ones.

The example about the cars is also outright false, the Tesla Shanghai Gigafactory for example is 100% foreign owned.

The only true statement you made was that you can't sell video games in China without a local publisher. Even so, I doubt the U.S. allowing foreign citizens to sell games without a local partner is the sole basis for your "We need to protect local businesses with protectionism!" argument.