"At first I thought this was an awful list, but then I filtered it by date up to 1995 and I felt that the list made a lot more sense. Is this an issue that it takes 15 to 20 years to get settle on what is truly worthy? Or is it an issue with the dawning of the Internet Age?"
I remember seeing the same thing on IMDB years back, where contemporary movies will appear very high on the list and disappear.
If you read the reviews (and I think IMDB lets you filter by demographics, or used to) you'll see that it's mostly young kids and idiots voting summer blockbusters as "10/10 OMG best movie evar!".
Not sure if there is a solution as it's always been the same way, there's always some hot new art, book, technology, etc. that's "GROUNDBREAKING" "CLASSIC" "AMAZING" that fades away quickly and the items that stick around for posterity aren't necessarily the ones that you'd predict (eg. Moby Dick and The Great Gatsby were initially flops on publication).