If it makes economic sense to break them down for parts and locking doesn’t stop it, I suppose that it might make sense to introduce security holes in phone cases, with a chain that links to a belt or similar.
Bonus – if you’re going to have a chain anyway, can maybe run a cable along it and have attached battery or other phone peripherals elsewhere on you that don’t add to phone weight.
There’s still the Fediverse.
I mean, that doesn’t solve the LLM pollution problem, but…