Physical hardware can be controlled, yes. Decentralization and obfuscation similar to TOR is probably needed here.
It is the same as free speech. You can say what you want, but you can go to jail for saying the wrong thing in many countries.
Shooting someone is also "just physics", yet many governments have been known to frown upon it (depending on the context).
More than anything, this is a good lesson in information theory. A blank sheet of paper isn't devoid of information just because it doesn't contain ink - rather, it is the context of the current situation that defines the information being conveyed. This is true in all forms of communication.
This reminds me of a story I read once about when Victor Hugo had just published Les Miserables. Just after publication, he went to his vacation home due to the controversy he was sure was going to follow the publication of the book. Wanting to know how the reception was going, he mailed his publisher a letter simply containing a question mark. The publisher responded with only an exclamation mark, and Hugo immediately understood - he had written an eternal classic.
(BTW, I read this in the book The User Illusion - a fantastic read)
> if they say no to your forgetting to scan the case of water on the bottom of your cart, you're going nowhere.
> if they say no to your hacked cable box, you're going nowhere.
> if they say no to your speeding, you're going nowhere.
> if they say no to your weed, you're going nowhere.
> if they say no to your growing a mushroom and mailing it to your friend, you're going nowhere.
There's a whole spectrum of how illegal something is to consider. People break the law every day for a range of reasons from accident, to ignorance, to convenience, to want, to need, etc.
If people all started talking through letter mail, you'd get Letter Control, they wouldn't just forget about it because it's not the internet. If the people somehow become smart and coordinated enough to move to some cryptographically-secure method of communication, your government will probably outlaw the equipment and actions associated with using it in the first place instead of trying to decrypt all communications.
The goal is control of information, and the way of doing that is to force everyone to use unsecured communication with no feasible alternatives. I wouldn't expect kid glove treatment with that, unlike speeding or minor shoplifting.
Treat social media as any other unsecured channel. You can do e2e on Facebook, you'll just have to do it yourself. I'm only half joking, I'm sure somebody has done this already, they just keep quiet about it.
Circumventing the Great Firewall in China is against the rules, comes with some risk for vpn operators and users, yet we know it happens regularly.
Buying and selling drugs online is illegal, yet there's always a Silk Road or Empire Market with enough buyers and sellers to make the risk worth it. We already have "letter control" for drugs, but it doesn't stop me from buying a QP of weed and a federal employee delivering it conveniently to my house.
Good luck outlawing the parts and software, maybe they'll get to them when they finally gather up all the fentanyl.
Even if chat control doesn't happen, the social internet is fucked. Just look at Quora for a preview.