You do have a good point, still, without a bit of making waves (advertising) and also getting a deal with some big chain to accept LTC as payment (to make LTC useful indeed), I don't see much happening.
Of course, there are also many other coins in top10 which don't deserve their spot. But long enough time will handle this.
I don't expect LTC go out of top10 quick and forever (if it goes out now, it may be for short time). But on the long term, more than one year, if they don't move then they will surely go out.