I don't think they will become "the next cornsnake" due to their high humidity requirements. It seems like a lot of beginners just can't take proper care of them. It also seems like a lot of people don't want to drop more than $25 on a pet. I sure hope I don't start seeing them in pet stores though.
I have to admit, my BRB is my first snake. But, someone who keeps a colony of GTPs (also extremely high humidity) got me started out and I'm not running into any of the problems that most beginners bring up. Before I got her I did a lot of research and made sure she was what I wanted, and also made sure that I felt I could take proper care of her (more reading and research!)
Plus, I just don't like cornsnakes! I didn't want to start with a snake that I don't love

I'm also not planning on keeping anything other than BRBs.