Three lines of argument are especially noteworthy:
“It is impossible to regulate cryptography.” or “Banning cryptography is like banning math.”
This argument misses the point in confusing the knowledge about cryptography with the wide-spread use of cryptography - or more specifically the use of cryptography to protect confidentiality. While it would be beyond the reach of governments to remove the knowledge about cryptography from the public sphere, it is certainly not impossible to threaten those that employ “illegal” cryptography with sanction.
This is exactly what happens with most regulation: Speed limits do not prevent the thought about driving fast, instead they address actually driving fast. It is behavior that is regulated, not thought.
So, similar arguments about the futility of regulation or the impossibility of enforcement aim a bit too high. Regulation does not require perfect adherence. Often it is enough if some people adhere to the specific law, and others can be punished in case of being caught. Again, speed limits are not perfectly enforceable, but they limit the number of drivers that drive recklessly, and it allows taking action against some drivers and thus nudging other drivers into compliance.
https://opaque.link/post/fog_of_cryptowar/
Shallow arguments don’t help anyone, they just marginalize the speaker beyond a narrow audience that already agrees with them.