All sanctions could fuel retaliation by the Russian government, the point is to punish them for their actions. Likewise the Russian government will spread propa

All sanctions could fuel retaliation by the Russian government, the point is to punish them for their actions. Likewise the Russian government will spread propaganda about all of the sanctions regardless of what they are. This would be a very tricky thing to "punish" and a tricky thing to implement in practice because this isn't a single government that would need to stop announcing these networks, but each private internet organization that is peering with Russia (think oversea cables and international peer exchanges). It could be mandated by governments for their own country, but to be actually effective it would have to be all the organizations peering with Russia agreeing to implement this. If one country or organization decides against the announcement filter you'd have to expand the route filtering to everyone that organization peers with. There would never be one target for the punishment. As for learning about the propaganda, a large part of what we learn is from Russian state TV and actors inside of Russia itself which this wouldn't impact. Since the major official propaganda channels have already been blocked on YouTube and the social media platforms, this would likely only impact the propaganda being spread through much smaller and harder to track sites if at all since posting of that propaganda could still be done from a cell or normal business internet connection. Some official government supported programs (such as the GRU hacking operations) already operate on regular business connections to avoid the direct association with government IP blocks, I have to imagine their propaganda machines do likewise.