Equal work for equal pay

The Australian Open tennis tournament is the sport du jour at the moment.

I have always wondered why the men play best of 5 sets at grand slam tournaments, but women still play best of 3. This is despite that fact that women have received equal prizemoney since the 70's and 80's (The Australian Open first offered equal prizemoney in 1984).

First of all, this means women's tennis can be very boring. How many women's finals at grand slam tournaments have been non-events, with 6-1, 6-1 walkovers finished in less than an hour, leaving large crowds with nothing to do but go home early and read books to the kids? The exciting 5 set marathons of men's tennis can never happen.
This has to change. There was a time at the Olympics that only men ran in long distance races, but now there are women's marathons, women's weightlifting, and woe betide any man who criticises women's rugby or boxing. Admittedly, Olympic swimming is still also behind the times. I believe that only women swim the 800m races and only men the 1,500m, but why? Come on gals try to keep up!!