It's slightly misleading to refer to Fidonet only in the context of Russia. It was popular in quite a lot of places around the world, not just Russia. Not even principally Russia, in its heyday.
These things are definitely systems to learn from, both their architectures and their histories; and people have already been drawing parallels to Usenet on this very page, notice.
When I said that Fidonet was a very popular alternative to internet in Russia as late as 1990s, I didn't mean that it was limited to Russia, but that in Russia particularly (well, FSU) it was still popular even in late 90s, while elsewhere in the world it was subsumed by internet.
These things are definitely systems to learn from, both their architectures and their histories; and people have already been drawing parallels to Usenet on this very page, notice.