Although there's still something of a gap in the way women and men are treated in tennis, it is generally fairly equal. Top female tennis players are generally as well known as male counterparts, they're paid similar amounts, they draw similar crowds.
Though there are a lot of female participants in sports like soccer, basketball, cricket, rugby, and so on, their numbers aren't as large as the men's, and they barely have five percent of the popularity, money, coverage or respect that their male counterparts do.
Why is this, historically? Was tennis ever dominated by one gender? Were there other sports that once had female athletes in the public eye?
Knowing nothing about tennis, how are men and women treated differently besides segregated singles matches?
Tennis has been fairly lucky to have a number of female personalities in the public eye, many of whom were hugely successful. We have Serena Williams now but going backwards there are various other greats of the game like Monica Seles, Steffi Graf, Martina Navratilova and Billie Jean King.
Why have they been in the public eye while big names in other sports haven't?
I don't know. But Billie Jean King might be why.
She was a vociferous campaigner of equal rights decades ago and had a great deal of success in this regard. There were even a famous series of tennis matches between her and male counterparts to prove that women were as good as men. All this must have captured the public imagination.
Unfortunately I do not know to what extent women's tennis was televised before and after Billie Jean King. That would be interesting to look into. It still took a very long time to reach equal pay though. I think that has only happened within the last 5 years or so.
With regards to other sports, I would suggest athletics also gives equal stature to men and women. Flo Jo, Jessica Ennis, Cathy Freeman, Marion Jones (although she was later disgraced, she was hugely successful before her drug revelations) to name just 4 female superstars of athletics off the top of my head.