And...Russia cannot move their own modules from ISS to another station due to the inclination differences planned. The hullabaloo over Russia threatening to pull their modules to create their own station turns out to be little more than noise it seems. You have to wonder why Nauka was launched then. After all, Russia could have saved it for the new station.
My understanding is that Nauka had to be launched because it had been so severely delayed that many of the components were reaching the end of manufacturer warranty periods which would have a snowball effect on launch insurance and the agreements governing the ISS. This had already been an issue which caused several elements to have to be replaced and it was on the verge of becoming scrap if it wasn't flown.
I very much doubt there'll be a long-term, independent Russian station post-ISS, on the scale of Mir or Tiangong. Technically it'd be well within Russian capability, but organisationally and financially, that's a totally different ballgame, unless there is radical change in the way Russia handles state aerospace projects. They might have a few basic, self-contained, short duration mini-stations drawing on the Salyut experience, but that's about it.
I think right now the most important thing for Roscosmos really really should be on getting Angara and Orel into regular service, then take stock and ask themselves what resources they've got and what projects they could realistically achieve with those resources. I'd love to see a revival of the Phobos-Grunt sample return mission. It's relatively affordable, technically doable, and would fit well into a ton of Mars research coming back at the moment, as well as be a huge win for reasserting Russian abilities in space. I doubt it'll happen though.