Sailing isn't sexist, but don't pretend that the sexes aren't different.
The great majority of sailboats in a given marina are owned by men, or if they're owned by a couple (hetero), then the man is the one who decided to get the boat.
If the man gets hit by a bus, the boat will be sold. Most likely to another man.
Women aren't excluded from sailing, but the female sailboat owner is still a rarity.
My husband and I have very different sailing histories. I was the SORC racer, he was the local small boat putterer. We both vetted our boat and it was a joint decision to own her.
Sailing doesn't HAVE to be sexist, it's just that men tend to have more time for hobbies in general. For instance, most working women I know who have a day off spend it doing laundry, cleaning house, etc. Men are more likely to be out playing golf, etc. Having said that, my own husband is very good at dealing with house stuff and having a hobby too. Our house has been something of a disaster since we bought our boat, but having cushions, sails, batteries, etc, is just part of the package, and I love sailing enough to deal with it.
Every person makes his/her own choice. If a woman wants to be a sailor/boat owner, there's really nothing to stop her. I know, I was lucky to have male mentors who respected my skills and didn't look at me as 'just another girl' but you make it what you want it to be.