It can definitely be profitable. The actual "product" Storj is offering is rock-solid. And I, for one, will definitely use it. My only concern is whether the public actually cares enough to be smart about their security. A lot of times, success is about who gets to market first. And with people heavily invested (space-wise) in things like Dropbox, laziness about moving could outweigh the protection they'd get from moving to Storj.
as i've said before, as long as the word gets about Storj, and as long as Storj itself is easy and accesible for the customer, we're going to see a quite a few people switching from other centralized storage systems to Storj.
If it's cheaper than centralized storage systems people will adopt it.