There is so much wrong with our junior system that a monograph could be written about it. There are two main dimensions to the problem.
The first concerns the Clubs in the NLA. They couldn't care less in developing their junior players because the NLA is the most attractive league in Europe for Imports, especially since the KHL is out of that discussion now for obvious reasons. So they just hire some imports wich are some best players outside the NHL as their "Star Players". Then they scrap together what they can their hands on on the Swiss market on overpriced contracts. Meanwhile they completely neglect their junior teams. (Switzerland has no independent Junior leagues like the US and Canada; every high level junior team is affiliated with a NLA franchise.) For instance they don't spend enough money on junior coaches on the lowest age groups. This means that the coaches that are hired are subpar and not able to teach those kids the fundamentals of hockey properly and they are already getting behind compared to kids from other countries like Sweden, Finnland etc. Part of the problem here is that there are not enough good junior coaches in Switzerland in general and training programs for coaches are subpar. But the NLA clubs have no interest in spending some money to improve those programs, or maybe attract some foreign coaches to mitigate that problem. When it comes to the older age groups, lets say U15 and beyond the coaches are a bit more competent. However at that level they are mostly concerned in winning a junior championship to better their own position and maybe move up in the within their organization. So instead of trying to improve their players individually and foster their creativity they just force them into a defensive system that has a higher chance for team success. Then finally at the pro level, most NLA coaches just flat out refuse to give young players significant ice time. This has a lot to do with the fan culture in our league. If a coach is not successful he will get fired fast. So most coaches don't want to take risks and always play a veteran over a young player so that they cannot be blamed for it if said young player should make a mistake. Lian Bichsel even explicitly said he only moved to Sweden because he knew that he wouldn't get to play a significant role on Biels senior team this season.
The second dimension concerns the Swiss hockey federation. The federation is an old boys club but the main problem is that most of the old boys are incompetent and complacent. They really handle the junior national teams the wrong way. It starts at the U16 level, the youngest age group for the national teams. Here they let the team only play against second, third and fourth tier nations. Germany and Austria are mostly the strongest opponents. There seems to be no incentive from the federation to play the top nations in this age group. So naturally they win most games against those nations, sometimes even by a large amount of goals and without any effort. Instead of competing on the highest level the players basically waste a year.
Just like with the clubs coaching is a huge issue here too. A significant amount of the people working in the federation are former NLA pro players. The coaches for the junior national teams are mostly not hired in regard to competence, but because of the connections they have with the functionaries in the federation. If you want to exaggerate a bit you could say that the functionaries mostly hire their buddies from their playing days. So you get hirings like those of Marco Bayer as the coach for the U20 national team, despite the fact that he had a terrible record in every coaching position he held previously. On top of that coaches that are competent but question the decisions and strategies of the federation like Thierry Paterlini get axed. The current national team coaches are also extremely authoriative towards the players. There are multiple stories circulating that U20 coach Marco Bayer was screaming at players in an overblown fashion, belittling their skills and straight up humiliating them. His predecessor Christian Wohlwend was the same way, maybe even worse. Everyone who observed him in any game behind the bench knows that he is a total nutjob. Finally there are also rumors that the coaches were playing favors when it comes to the roster composition for tournaments like the WJC, Ivan Hlinka Memorial etc. Apparently players that had relatives who knew the coaches or key people in the federation were selected over some other players who were maybe more deserving. I have no hard evidence on that last point but it wouldn't surprise me at all.