It’s not about what Russians can get from the outside, it’s more about what they can get to the outside.
I think the idea is to have some capacity to temporarily preserve some connectivity, while mowing down protesters or something like that.
They are doing such exercises for like 10 years btw.
But when the war in Ukraine stops with some “mission accomplished” ceasefire, there will likely be more violent signs of popular disagreement with Putin. Because, well, people with combat experience will come back. Some of them to ask for money on the streets, some of them to abuse their relatives and neighbors, and some of them to do crime, and some of them probably to stir shit up.