Thats about the only one, care to mention another that has any sort of market share, Don't mention island packet, tiny tiny numbers sold in Europe.
The reason you see European boats in charter and elsewhere is that European completely dominate sailboat manufacture. Just look at the number of manufacturers, including the giants of the industry.
The US per head of population has a very small sailing community, In Europe its considerably bigger. The big sectors in the US are small sports boats and in this the US dominates,( at least 6 big companies) outside of that it is a European game.
You are right about the bigger interest in sailing in Europe and I agree that it gives to the European boat building a bigger dynamic. But we were talking about bias or not, versus a tendency to like more modern boats, opposed to a more North American conservative taste.
I think it is not by accident that the American boats with bigger acceptance in Europe are the JBoats. They are not only modern by design but also with technological advanced building techniques…and they are not cheap. You say that it is the only one but on a smaller scale Corsair trimarans also sell well in Europe, considering the proportion of boats sold in Europe and the US. Another modern design.
Yes you are right, Island Packards, Hunters, Catalinas and Tartan have tried to sell in the European market and even if the boats are known here, tested by sail magazines and on the main boat shows, they sell very few boats. The design of those boats is more conservative than the design of European boats and it is significant that the place where some sells happen is UK that has the most conservative market in Europe, in what regards sailing tastes and boats.
You can see that while European boat builders use the best designers all around to design their boats and the same brand uses many times different designers, including some Americans, American boat builders design the boats in the house or have traditional NA that design almost exclusively those boats.
That makes for a much bigger evolution on design versus a more typical product on the American market, meaning for instance that an Island Packet is a type of boat with design characteristics that have been maintained through the years while you cannot never know what is going to be or look like the next Benetau Oceanis or Benetau First, except that it is going to be designed by a top architect and is going to be actual, modern and it will sail very well.
Things seems to be changing on America and new Tartan or new Catalina look less similar to previous models but those factories did not yet gave the leap to command some of the best world NA to do their boat designs. I truly hope that it will happen soon. I think it would make American boats a lot more appealing and interesting, at least in what regards an European perspective and more modern for sure.
I really think that is the main reason, a difference in taste, more conservative versus a more modern one.