I'm a Gen X'er and I've been playing pinball since I was a kid. My dad had a gameroom in our basement when I was growing up and now I've got games of my own. Even way back then, I didn't know anyone my age that was into pinball. Shortly after, stand up video games got popular, and then the game consoles came out.
I know there's a lot of people on this forum in my age group that are really into pinball, but in the grand scheme of things we are a huge minority. There are enough enthusiast out there to support a niche' market and I think Stern has responded to that. I don't know what the percentages are between games bought by operators that go out on a route and games that go straight to someone's private game room, but I would guess the latter has a bigger percentage than it did 30 years ago.
In a way, I like the fact that pinball isn't all the rage. If gives it a certain uniqueness.