If Durov is liable for crimes committed on his platform how far away are we from making phone companies and ISPs liable for crimes committed using their services? This is a very slippery slope. I don't see a problem with requiring a company to cooperate with a court order to release data. However if a company does not have this data (because it's encrypted) it should not be liable or be required to collect such data.
Very far. but france is a civil law system. (https://en.wikipedia.org/wiki/Criminal_responsibility_in_Fre...)
if you don't comply with legally valid requests, then you are going to be held liable for it.
But thats the same in common law as well. If an hosting provider in the USA refuses to act on reports of hosting copyrighted material, then they are liable for damages. Safe Harbour has its limits.