China still does not have many companies on the level of American technology firms. Just restricting foreign competition in the domestic market is not enough for most places to compete; their domestic markets and investment levels are too underdeveloped to produce globally competitive companies.
The thing that produces competitive industries is requiring them to compete globally. That's how Chinese cars got good (Tesla joint venture -> independent Chinese Tesla -> competitive domestic companies).
There are two main reasons why the EU struggles to produce strong text companies are, IMO:
1. EU laws and regulations are very burdensome and cover everything from employees to packaging waste.
2. There is not enough capital that gets invested in EU tech companies to pay high tech salaries, again largely driven by more restrictive financial rules.
The result of these two is that European engineers tend to leave for the US, and European companies struggle to grow to American size.
Around 70% of American billionaires made their money themselves, while in the EU a similar share inherited it. Despite all the talk about social mobility in Europe being better than in the US, the truth is that the ultrawealthy in Europe have created a regulatory environment which makes it nearly impossible for real competition to exist.