Well we have the fortunate ability to remember these films, tv shows, etc. they never go away whereas during the 30's, 40's, etc. they did. They might show up on occasion on the bottom of a two film bill. By the way there were remakes for old radio shows as well with the same projects that were popular recast and redone. It's not exactly a new pheonemena just one that is more obvious now and with our short attention span, need to have comfort films. The reality is that studios are scared of taking a risk even more than they were before and even their low risk projects aren't paying off.