The Russians will never be more powerful than the Italians in New York because even if their powers or their monopolies are down there are two extremely powerful families whose forces are still very high which are the Genovese and Gambino families and even if their powers were to weaken there is the Ndrangetta which shows its nose little by little and I think that in twenty or thirty years the Calabrians will be very powerful and will have passed the Sicilians as it is currently the case in Montreal and in Canada.
The main rivals of the Italians in New York are the Albanians who have not hesitated to attack the families of New York in the early 2000s the problem is that it only takes a mass arrests for an organization and these no longer exist to the contrary of Italian families.
For the Russians they would have more chances in other cities than New York as Chicago Los Angeles Detroit ...