My only real issue with bunkai is that like anything else, once you learn what a given move "means" you have to practice it. And many applications of the kata require a partner to work with---and all to often many people don't have a regular/reliable practice partner.
I was always taught that anything that you can do in kata you shold be able to do on a heavy bag (more of less) so I often pull the techiniques "out" of the kata for haevy bag practice.
I find the kata a good way to keep the PRINCIPLES of the style and techniques used in practice--a kind of mneumonic device if you will.
Plus they are a lot of fun.
Wouldn't say that I practice kata for the sake of doing so however. I--speakig just for me here. And feel free to disagree
I find value in the practice of kata, I see gains in its practice and I think they are useful....TO ME.
If others don't?
Then don't do them.