Russians have know-how to build medium sized carriers , at slow pace (one-by-one) . Question is what are they going to do with them ? In current situation they could operate 1 or 2 (3 would be a stretch ) . That is not enough to effectively oppose US & NATO . In case of war main role for them would be to defend own submarine bastions - mirror of the Soviet doctrine . In such case they would again have to be armed much more then their Western counterparts (SAMs , ASMs , ASW weapons etc .. ) sacrificing aviation facilities .
On the other hand , there are those in Russia who advocate aircraft carriers as international diplomatic tool . Sort of , Russian ships sailing across the world (in peace time of course ) , promoting Russian interests . Such fleet could be useful against less sophisticated opponents in neo-colonial interventions (so called peacekeeping) , but not in "real" war . In that scenario question would be how much resources should they pour in whole program - would one aircraft carrier be enough in order to save money for more important things in armed forces ? Or they still need two to maintain prestige ?
What makes you say that the Russians are able to build a medium size carrier about 50000 tons ? They needed about a decade just to deliver the 45400 ton Vikramaditya. And that was a refit. All the Soviet carriers were build in the Ukraine and other components are build in other ex-Soviet states. Those companies have long closed their doors now.
