That's why I think it's pointless to try and just have mass starts and short races, almost no skiathlons and relays. If you see that you aren't drawing in as many new fans as you had hoped for, then you should rethink your strategy and stop antagonizing and pushing away traditional/old fans of the sport. If you start losing those, then you are in serious trouble. That part heavily falls on Mignerey and FIS.
The performances of non Norwegian/Russian teams and individuals has many possibilities, as zarnack said, funding and public interest are huge. Climate change, travel expenses and simply other sports being more popular is something else that hinders progress of xc skiing in the rest of Europe and elsewhere. Now, I don't think xc skiing will ever become much more than a 'fringe' sport in North America. It hasn't in all the decades it's been around, even when winters were good, even when the American men were doing really well in the 70's and 80's with the likes of Bill Koch, and in recent years the American women with Diggins and Randall. If it is improving, it's improving very, very slowly that it's hardly noticeable. There are good organizations like Fast and Female, which was founded by Canadian Chandra Crawford, which can be found at various post race events around North America, but how big of an impact is that and is it short term or is it long term?
French biathlon is at an all time high, it seems, while French cross country is barely relevant with only Chanavat and occasionally another sprinter or distance skier like Manificat (predominantly in skate) making headlines.
In Italy it's pretty much only Pellegrino flying the flag, and he, like everyone else, has been mostly shut out of the medals by Klaebo and the Norwegians.
The Swedish women can and have challenged the Norwegians, particularly in sprints. The men? Not so much. They just don't have the quality or depth. Their old stars are either retired or are past it. Rickardsson is almost 38. I don't see why he is still racing. Yes he can make the team, because he is better than most of the youngsters, but it's a bit embarrassing for them that they can't find anyone else. Halfvarsson is more sick or injured than actually racing. Burman is the only constant one, but he rarely gets into the top 10, and a podium seems so far away.
The American women can challenge and have a nice group of U23 and U20 racers coming up, so I think they will be ok, but will they improve their classic skiing and races over 10km? Their strength is primarily in sprints and short to middle distance skate races. The men right now are not doing well, but they have U20 men coming up that could fight more regularly in the top 30. Time will tell.
The Russians are the only team that can seriously challenge the Norwegians, at least in the men's races. Bolshunov, Ustiugov, Spitsov, Yakimushkin, Belov, Retyvikh, etc...they have the talent and the depth. Just have to get their tactics and ski preparation right Their women's team is being bailed by Nepryaeva's consistency. Just a real pity she got sick just before the ski tour and was unable to continue after Ostersund. They are missing Belorukova, Sedova and Soboleva (all due to pregnancy), while U23's like Istomina (injured), Durkina (poor form, perhaps overtraining), Zherebyateva (see Durkina) missing in action have hurt Russian chances for good results in the women's division. If they get all these skiers back for next year, and are healthy then I think they'll have a strong team.
It is depressing to see one country dominate so much. Having the top 6 and 8 men in the top 11 of a tour is not good for the sport going forward. The women's division sees 'only' 5 Norwegians in the top 10, but the top skier is way ahead of anyone else.
So it's like what came first, the chicken or the egg? Does Norway's funding, resources, manpower that gives them dominance demoralize everyone else, or does everyone else's lack of funding, resources and manpower demoralize them that they either can't perform well enough and/or simply can't field skiers which makes the fields weaker which enables Norwegian dominance?