I think the interest got higher because they realized there are tons of people who could invest in global tokens or currencies from everywhere in the world. So, Russia knows that they could make a digital currency that means nothing and worths zero but could get millions of dollars for it, maybe even billions. Which is why they are looking into it and nothing else.
However, some of the other countries like Japan for example is doing it because they want to see their country develop into something better, they are not a ruthless capitalist country, they do have a very high standard of living and cost of living but they do have a very tiny unemployment as well so they want to improve the finance world to the level of their own with digital currency implementation.
I feel a lil bit of hate towards Russians.
But seriously, when these blockchain projects came into fruition, we encountered a lot of Russian scammers. There was a time that if it is a Russian-backed crypto, expect that you will be scammed. They really have bad reputation in the community.
But for countries like Japan or maybe Singapore (which I am surprised that it is not included in OP's list), they are pretty serious in exhausting the potential of blockchain towards the development of their country.