Very interesting discussion...
I have never ridden trains growing up, and even as an adult only very rarely, yet I was motivated by model trains as a kid - Lionel. My son has never ridden on a train and he loves his Brio/Thomas and now Märklin trains.
I think that wherever there are a lot kids with relatively high income parents, you have a potentially large market. But that market needs to be developed - it does not require millions of dollars to improve on basic channel management. Märklin has a lot of room for improvement in the US and probably many other countries - this represents a huge potential for them - if they can get serious about it.
The cost of the products are also important, because you obviously need to make a profit (the bigger the better), but if you charge too much, then although the parents are well-off financially, they will opt for competing products or activities for their kids. Today, kids have many options for entertainment and hobbies - ie video games, movies, sports, etc... Children can and should have a variety of activities, but if Trains are going to cost thousands of dollars for a couple of digital starter sets - then most parents, even in the relatively affluent courtiers of Western Europe, North America, & Japan will simply not go for it.
Furthermore, the model trains need to be appropriate for today's generation - they need to be plug and play digital and with sounds - this the computer & video games generation.
I wonder if there were good digital starter sets with sounds (for example the 29571) readily available in hobby shops and toy shops for $149 USD - how fast would the fly off of the shelves. I live in Northern California and I have seen this set in shops for ~$600 to ~$700, and I have seen parents who are very interested in purchasing it for their child shriek and gasp when they see the price. I know it is available via the Internet for less, but most new entrants into the market will not look at the Internet first.
This may seem like impossible simultaneous equations to solve - however, the opportunity is huge and Märklin has a strong foundation and more resources than many other companies had.
You can look at some the more successful companies of today - and they probably had more impossible conditions back in their history, than what Märklin is facing today. Yet some of these companies despite their challenges, or maybe because of their challenges, they made bold changes and transformed their companies and created the brands that we now take for granted. Consider the likes of Nokia, Sony, Honda, Nike, etc... Today these companies spend many many millions of dollars on advertising and brand maintenance and brand building, however, that is not how they got to where they are. They built themselves up from humble beginnings - many times they saw markets and opportunities that other did not see or did not want.
In my opinion, Märklin management needs to have the will to make the necessary changes, and they need to focus primarily on the kids (their future customers) or the parents of kids, and not put so much focus on us 'old timers' nor the us collectors. These customer groups all have value and they can overlap, but Märklin should prioritise their future, and that is the kids.
If Märklin were to be more effective at leveraging the global supply chain and the global market place, they can begin the process of transforming themselves into a truly global brand. This will not happen over night, but it is possible.
For the sake of Märklin and this hobby, I hope the best for Märklin and their management.