The 'apart' in apartheid refers to separation. Black people were forced to live in different areas to white people. Unless women are forced to live apart from men and in different areas it's not the same thing.
More generally, though, don't you realize how badly it comes off when we're talking about a truly terrible situation for millions of people, and the only contribution you can offer is some semantic nitpicking? Do you really think that is being helpful or productive? Pick your battles, man.
We're sitting here talking on a discussion board. The readership of this site in general is not in a position to do anything about the fucked up situation in Saudi Arabia. We are in a position to do something about people (arguably) misusing language in our own back yard.