The women used to play best of 5, way back in the early days. It was changed largely because men complained about having to wait for women's matches to finish. (I'm surprised they didn't shorten it furhter.)
I don't like the idea of a changeover to a lot of b/o 5 matches. For one thing, it changes the way the tennis is played. The women tend to try to win every point. They go all out. If an opponent is serving at 30-0, she's digging in and trying to win the point. The men tend to go into "flail" mode in this situation, and just swat at the returns. If they get lucky, and a couple go in, then they'll try to win the game.
I go with the reverse idea as well. Reduce the men's matches to b/o 3. That will, over time, improve the quality of the matches. And the fact is, you almost never see a match with 5 great sets of tennis. Even the legendary Borg-McEnroe match did not have 5 great sets. Instead, what often happens is that a lot of matches are twice as long as they should be without being any more interesting.
Best of 3 favors the more skilled player. It also means you get to the drama more quickly, as a player losing the first set is on the brink of elimination. And if the match is a blowout, it's over quickly. The only thing worse than watching a match that's bad and/or uncompetitive is having to watch it at least 50% longer.
Best of 3 also helps with the scheduling. It's easier to keep a tournament on track. And it would allow spectators and TV viewers to see more matches and players. This would allow audiences to build up familiarity with players who aren't from the "home team".
Anecdotal evidence suggests the public at large doesn't care for a constant diet of b/o 5. Whether it's a player-turned-writer frequently overhearing fans say they'll "come back for the start of the 3rd set", or an official citing TV data showing fans switching away at the starts of sets on a regular basis. By reducing to b/o 3, it increases the urgency of the very first set.
Sure, by doing away with b/o 5, you might sacrifice a few upsets, and wind up with a few more blowouts in the early rounds, but it would pay off in more late-round encounters between the best players. And, let's face it, it's the late-round great matches that stick in the public consciousness for a long time.