If they’re turning to nukes that means they’ve conceded conventional warfare. How is this possible given the disparity of conventional forces between Russia and Ukraine? It can only be that the Russian military does not approve of their role in the invasion and Putin wants to avoid the public embarrassment of more Russian soldiers defecting.
There is something very deeply wrong if Putin would have to use nuclear weapons to defeat a nation it kept weak since the collapse of communism and the return of the Czarist/Soviet/Putinista-Reich. Maybe the volk are not willing to kill their neighbors for Putin’s glory.