> Such laws cannot be enforced. Enforcement can only be arbitrary.

I am against criminalizing cryptography and largely agree about it being infeasible given the extent of proliferation and ease of replicating it/am playing devil's advocate:

Laws banning math related to manufacturing nuclear weapons can and has been enforced. It's important to take legal threats like ChatControl seriously and not just dismiss it as absurd/unenforceable overreach, even if that's likely true.