I don't know how it would've manifested itself, but I think Trane probably would have commercialized his music more greatly in some way. If I'm not mistaken, before he died he expressed regret at losing his audience. Of course, there's contradiction there because he also recorded some seriously out shit not long before his death. Still, I have to wonder...
Here's my perspective. The idea of mass appeal, at this point, is fairly hard to stomach - other than obvious pop crap (= pap), music has become a highly nichified thing. "Real" jazz, as well as "real" rock and roll and other types of music, has a small, steady and cultured audience. It may not grow, but it shows no signs of disappearing entirely.
The problem with a niche is that there are still a fairly large number of artists competing for a few gigs and a few record sales. But I think Wynton's pretty much entirely out of that picture.