EU is doing similar with anti-trust rules and rulings. It is their right to regulate commerce in their jurisdiction, even if that means fining Apple based on world revenue/profits rather than EU revenue/profits.
Or China! China has definitely prohibited American companies from reasonably operating in the US. Reciprocity there makes sense but it does seem that this sort of reciprocity is going further than China had, no?
If they passed a law requiring US companies operating in Europe to divest their ownership in those subsidiaries or be banned from operating there then that would be their right as a government. Isn’t the EU rather famous at the moment for forcing foreign businesses to comply with their laws and regulations? e.g. GDPR
That said, so long as you don't have data centers in the country, what can they realistically do to stop you if you have a VPN?
There's nothing illegal w.r.t a private citizen trying to circumvent censorship afaik. If you're trying to use illegal content or services (hitmen, drugs, child porn, non us compliant crypto such as finance etc), then I can see the retribution, but unless you go full middle east/CCP people will still get access to and repost it