Some people would question the relevance of a 40 year old style of play when it's to be applied to the play of today.
1. We hit harder now.
2. Cement rec courts are fast, yes, but most tourney's are played on slower surfaces.
3. The big changes in racket seem to favor a gain in groundies as opposed to any gains in volleys.
4. A topspin lob is often seen even in 4.0 level tennis.
5. It takes much longer to learn an all court game than just a baseline game.
6. Try if if you dare, don't expect to win too many.