They could just go whole hog and ban all unsanctioned encryption, and if you want to run a business in Russia, you must submit to the Mother or not do business, period. That'll make nearly all forms of encryption stick out like a sore thumb. Even stego's gonna be hard to get past a well-conditioned traffic sniffer.
Really? How? Come on, you talk about this a lot, how about some actual ideas of how it would actually happen?
Eg how can you tell "encryption" from "damaged packet", "game data", various video streams, "stego" (which doesn't stick out at all, have you not noticed that there's a huge number of file formats that collect garbage, such places being great for "stego" for a start).
Given that Russia is a significant trading country that uses encryption to protect international trade, how then will it work?
Russia also has boarders with other countries that aren't under the thumb - line-of-sight optical or radio networking can be built (like dissidents have been doing for decades) - how is your magical catchall going to stop or even really slow this stuff down?
Would love to see some ideas. Got friends I'd love to stay in touch with and if you have any reasonable ideas how it could be done, that helps us get ideas to circumvent.