Maybe he's right but I'm not convinced. I think kids/teens would love to go the theater more but my personal anecdote is that my friends and I lost interest after age 25. It's just not as exciting to go to a theater when you're not in high school or not part of the dating scene in college. Of course, if you're a parent with young kids, you go because you're the chaperone for the Disney movie.
It seems like declining visits by adults is just a general long term trend. Similar to the decline of drive-in theaters. Used to be fun to to drive the car into the lot but the novelty wore off. Adults also went to theaters in 1930s in high numbers (e.g. Gone With the Wind) because theaters were among the first to have air conditioning which was a big deal. Every house has air conditioning now.
Lastly, the economics of movie theaters have created a feedback loop that results in "big tent pole" films like Disney / Transformers / Star Wars dominating the screens. Adults want serious drama like "House of Cards" -- which is available at home.
One could argue that if ticket prices weren't so high, more adults would have gone to theaters which would then have subsequent effect of HoC, Boardwalk Empire, etc only being released in the theaters. I guess one could go down that rabbit hole of an alternate universe but I'm not convinced by it because I still think adults just eventually get bored of the "theater experience". (Babies crying in the back row, other patrons who don't shut off their cellphone ringers, sticky dirty floors, 15-minutes of ads before the movie starts, etc)
EDIT ADD: some replies seem to misunderstand my comments. I know some people do enjoy going the movies and the barrier to that is the price which MoviePass solves perfectly for them. I'm not arguing the existence of such moviegoers. Instead I interpreted “People really do want to go more often,” as a _macro_ trend and my comment is about reversing the macro trend of declining theater attendance. I'm not convinced MoviePass will actually solve that because fundamentally, the thrill of going to the theater wears off (age, Netflix/HBO at home, other entertainment distractions competing for time, etc). Again, that's a macro prediction. Yes, there are lots of enthusiastic moviegoers but they're outnumbered by the people with apathy for attending theaters.