Just based on my own personal observations, a vast majority of the comments on the Carowinds fb page doesn't seem to be too happy about this either, so it can't just be the "fanbase" that's displeased. This really is an overwhelming head-scratcher for me. Thunder Road is a classic, and was probably one of -if not the first- rollercoaster most kids from North and South Carolina ever rode. (Hell, It was my mom's first, and she rode it with Donnie and Marie Osmond!) It's really unfortunate that this is happening.
The management has to know that this isn't a decision that will go over very well, so either the payoff will be worth it (more so than we can even imagine) or there's more to the story than we know. I find it hard to believe that a waterpark expansion takes priority over preserving the best wooden (and furthermore one of the best in general) roller coasters at the park.
I won't be the one to bring up RMC, but that would be the only reasonable reason to rip out such a classic Carolina icon, IMO. And since I find that unlikely (to say the least), this announcement really bums me out.