Well, the most obvious aspect is that most listeners of "popular music" these days are more into the "beats" and sounds than the lyrics/stories. I'd imagine that's what more or less started the trend way on back and it just became overwhelming as overstimulation became more and more the norm. When the solo ballads were "a thing" people were far more lacking in "things to do" or really all that many options in general. Any "revivals" have mostly only been "big" amongst a relative few. By far the most general public success with the revivals were primarily with the more saccharine examples.