What future? Between the war in Afghanistan in the 1980s and the collapse of the USSR, Russia has only a few generations left before experiencing demographic collapse.

There simply aren't enough young men there to keep the Russian population growing and the population there doesn't value diversity enough to consider producing more Russian children with immigrants.

This is what many believe (e.g., Peter Zeihan) to be the real reason behind the invasion of Ukraine. Ukraine is "Russian enough" in their eyes, so combining the two populations would help stave off demographic collapse.