Difficulty used to also be used to add longevity.

If a game was moderate in difficulty in the NES games, it'd be completed in an hour or two. Make it really difficult however and have no continues meaning you started from the beginning when you died, and it suddenly took a lot longer to see the end of that.

We no longer really need the high difficulty as a staple for longevity, if anything IMO games are getting too long now. If you made them just as brutally hard, only about 1% would ever be able to see the end of them.

Am i an alien? I like hard games......

I think plenty of people like hard games, but there is a lot that like easier games too.  Could be bcause they want to see the story without dying a lot, or could just be a skill problem and the lack of trying.  Maybe they feel hard is too cheap, idk.  I think people will give you different answers. 

by making you replay the whole game the game basically trained you to play, you had to learn that game.

Touhou? That game was made in Hell! T_T

Well, to be honest, I've never been fun of overly difficult games. I always get easily frustrated if a game seems harder than necessary. That's the reason why I never finished any Mario, Sonic, Donkey Kong, Mega Man or Comandos games. And I recognize that all those are great games, but I just got tired of doing the same thing over and over again until you got to pass a level.

Now with that being said, I love puzzles games and having puzzles on my action adventure games. And the harder the puzzles are the better. Now with those I get that feeling of accomplishment when I get to finish them.

There are two kinds of hard games, those that are hard because the challenges are very difficult, and those that are hard because the journey towards their end is very long and possibly with many sidequests and/or open worlds.
Devs, pushed by publishers, make very few of the difficult ones for fear of scaring away many gamers, and they make very few of the vast ones because making them, particularly in high res, may cost a lot of money.
Oh yes, I forgot mentioning games that are both vast and with very difficult challenges... Well if we find one, we can forget finding another for a few years.

Touhou is a piece of cake when compared to Ikaruga.

Only thing which was difficult on NES games was to gather enough interest to memorize the things you are supposed to do.

No love for Psyvariar?

Dunno what that is, but sounds kinky!