

If your browser and device has a state sponsored CA certificate it’s not trivial to bypass. Transparently all certificate traffic could be intercepted by an ISP. Look at Europe already trying. Once someone malicious (to you) is a trusted certificate issuer you no longer can verify either the destination nor the privacy of the content.
Ssl based vpns are also decrypted. And vpns which use public key for identification would no longer be trusted.
They could be, but I assume say like an apple device won’t install a ccp root authority unconditionally. Huawei and xiamoi probably could be forced, but the browser too, like Chrome, Firefox and safari need to also accept the device certificates as trusted.
But the pressure in Europe would likely be to trade within Europe, you must comply.
It fundamentally destroys the whole trust of PKI if this did go ahead. We just need to hope it does not.