Matter of taste, I believe... For me this public floor wouldn't be a waste. You could have boutiques, newspapers stand, florist or cafe, you name it, similarly to ground floors. When you have 50 floors "wasting" one or two for the connection shouldn't be a big deal. Of course everything boils down to how well is it designed and implemented and how many people actually uses it. In my place there are skyways between big department stores. Only two and not that spectacular but it works nice, is convenient, doesn't spoil overall architecture. I'd gladly see more such solutions in future.