I don't think success like this can be explained by company slogans. They do indeed have very impressive quality and creating parts with the required precision cannot be achieve with a random deep-drawing plastic process.

But I believe a large part of their success is due to being at the right place at the right time. They also had very good marketing. They keep themselves present with all their branded stuff, even if their standard palette is probably far more successful. And they seem to put a lot of effort in their models.

Curiously, some other hobby markets like miniature trains seem to allow for more competition, even if the market is so much smaller.