If this were ever to happen, the only people using secure (deniable) cryptography would be be the bad actors. Everyone else would be screwed.
You and I understand that, but how many politicians understand that? We constantly ban stuff that's futile to ban and make things worse I the process.
He says that to avoid this to happen the citizens need to demand access to strong cryptography.
[0] He writes about it here (danish to english): https://translate.google.com/translate?sl=da&tl=en&js=y&prev...