The Russians have essentially no fleet now. Long term direct support would be difficult. Proxy support through the Cubans is their only viable choice. But is that really worth it, the Cubans will demand their cut those driving Russian costs up. How long will the current Cuban regime stay? Raoul is no spring chicken either. The Russians may be making a long term calculation that its not worth a big commitment.
Good points. In any event, China is making its move all over the world.