Do you think that Pushkingrad will ever make a serious attempt to "reclaim" what's left of European Russia (except for the parts that everyone is carving out for themselves) after NATO is done combing over the remains?
Russia in Pushkingrad only continues to exist due to goodwill and the need to have a 'legitimate' successor state. They do not have any means to carry out military actions without massive support from NATO.
But once the dust settles and countries like Finland, Ukraine, the Baltic states, and the newly formed ethnic states are done carving out pieces of Russia for themselves, there's still millions of people living in a nuclear wasteland.