I think it is cool. I have never had my hair cut there (usually with people who are one-timers and trying to get attractions in), but I have stopped there several times, and I have been with a marine that needed a cut before he went back home and to base. Ironically, they could not give him a shave, just a haircut. (I thought that they were full-service and could do the shaves, but not at least at that time a few years ago.) But it was a cool experience.
I think a barber shop is central to "Main Street, USA," and should be the "home port" of the barbershop quartet. So, I don't see it going anywhere, but I do understand people's trepidation, given WDW's recent history of cutting corners and taking out some of the small details that many of us seek out, and which made us love it in the first place. It was an example of going the extra mile for authenticity and service -- helping to make WDW the gold standard, which they should maintain.