Huge numbers of cinemas closed across the country (and beyond) in the 80s and early 90s because people stopped going to the cinema so much - advent of videos and so on.
For whatever reason (and I have no idea what the reason is) cinema going habits have swung back again in the last 10/15 years. Yes, a cinema in Forest Hill is a "nice to have" rather than an essential and perhaps the Capitol is not the right venue but I think White Elephant is a little wide of the mark if you mean that ANY cinema in Forest Hill would quickly become one.