"Most Russians" and "casual fans" are not the same thing. If you are a fan of hockey , even a casual one, you know that the NHL exists. There's a big difference between being a casual fan and someone who doesn't follow the sport at all. One implies that you pay at least *some* attention to the games/team/sport. The other just means you're Russian. You said casual fans don't know the NHL even exists, and I'm calling bs on that one because I think anyone who is even pays a small attention to the KHL knows that the NHL exists.
If someone doesn't know anything about hockey whatsoever, doesn't follow the KHL , etc then yes, maybe they are completely unaware that there are professional hockey leagues at all. I still think anyone who could possibly call themselves a fan in any capacity (even casuals) know of the NHL's existence.
When the poster above asked what the feeling was like in Russia, I assume they mean of people who know enough about hockey to know who an 18 year old prospect is, not just randoms off the street lol. Of course there will be people who don't know or care about hockey in any capacity, there are tons of people in Canada who have no idea who Connor bedard is or that the Blackhawks won the lottery, but I would say any "casual" fan of the NHL is aware that the Chicago Blackhawks exist. Unless your definition of a casual fan is someone who pays no attention at all, which I would call non hockey fans.