I find it astounding how BTS have managed to go through myriad concepts and genres without it denting their popularity even a little bit. They have successfully traversed across so many genres that now they are no more bound to any one and do not have to worry about going too far from their core sound and disappointing the fanbase as they are no longer defined by one type of concept or sound. I feel this, amongst many other things, sets BTS apart from a lot of other groups which tread dangerous territory when they experiment.
It is one thing to take a risk but with BTS their gambles seem to have paid off giving them so much liberty that now they are not constrained by one type of music. It also makes fans more excited for their new music cause we know they can experiment with many different types of genres fearlessly and hence there will always be something new to look forward to.