I also found it interesting that when I was auditioning speakers, my personal favorites tended to be the least sensitive designs.
This is not too surprising. Most speaker manufacturers today look for small drivers that play deep in a small cabinet.
As Dennis pointed out, all things being equal, higher sensitivity drivers do not play as deep. They also tend to require larger cabinet volumes. So, if you were a driver manufacturer, would you put all your R&D into higher sensitivity drivers that don't play as deep and require larger cabinets? Not if you want to sell very many. So it is not surprising that the latest state-of-the-art drivers tend to be lower sensitivity drivers.
There was a time when amps were not that powerful and there really wasn't a choice. But today, watts are cheap. So if you want a speaker the the best-of-breed drivers, you will probably end up with a lower sensitivity speaker requiring more power.
Of course, another alternative is to use multiple drivers, but you end up introducing all kinds of comb filtering issues in the process. As I've said many times in the past, speaker design is all about balancing trade-offs. There is no free lunch.