re: Were the early Horror Movies Scarier than the ones Nowadays?

I think the problem with that question is that 'horror' isn't a monolithic genre. There are definitely edge-of-your-seat thriller/suspense where what's not seen is scarier than what is, but that approach really doesn't work with, say, a post-apocalyptic zombie movie, for instance. It can work for a portion of the movie, but nobody really wants to watch "Nightmare on Elm Street: Freddy's Really Embarrassed to be Seen in Public" or "The Shining and What Happened When Jack Decided to Head Home Alone Because the Hotel Was Boring Him."

And, honestly, some people are just as freaked out by visible, visceral horrors as others are at harmless jump-scares or shadow-puppets. The alien can be just as frightening as the unseen. Seeing somebody with his guts ripped out isn't subtle, but it is disturbing and can be every bit as horrific as just getting a hint of what happened. If these approaches didn't also work, those sorts of movies wouldn't get made because nobody would bother paying good money to watch them.

(And speaking of alien, 'Alien' is an excellent movie to make this point with. For a large portion of the movie, we don't get a clear look at it, though we did see the results. Had the movie stuck with that to the bitter end, it wouldn't be anywhere close to the acknowledged modern masterpiece it's currently considered. 'Jaws' did much the same thing, but it can be argued the approach used was perfect...for that movie. It's not safe to assume the same logic works for every movie.)