I don't think I'd make a great starship captain, so I don't think I need to see someone like me onscreen in Star Trek. I need characters who are believable and who have some qualities I can approve of or sympathize with to some extent. That's not limited to middle-aged white guys.
I do remember people on usenet years ago complaining that pandering to the politically correct meant they couldn't watch DS9 or Voyager, because everyone can relate to a white man in charge but only black men can relate to a black man in charge and only women can relate to a woman in charge. It was almost funny to see people so obliviously blind to their own racism and sexism. Well, not all of them were oblivious -- in my experience, most people who blather about the PC police are outing themselves as bigots. (I'm referring to the extreme cases on usenet in the 1990s, not to anyone here.)