Over the years some movies that where great hits for their time, but most films did lose that little spark that made the big hit for there time. The Terminator is a good example of this problem. Once a great horror film. Now a average Sci Fi / action film. Aliens can be be put in the same boat, but it had 2 great films, an OK film & a not great idea one.
There are a lot of films out there that has not lost the spark in what made them so great & most of them are part of my childhood. That made me believe in those who made a lot of great movie. Some of those may have pasted away since them, but there work will live on.