It's not an overstep for the US to say "we get to say how American companies behave". This does not translate to "say what devices are available in every country", though - if Apple China can manufacture iPhone by itself, it's welcome to it. Ditto for the Great Firewall. But if the company profits in US from practices that we consider bad, I don't see what's the problem with cracking down on that company.

More abstractly, corporations are artificial legal entities that are created by governments in the first place. So why can't governments restrict what those artificial entities can and cannot do?