Some of those old games from the NES or even into the SNES era were just outright impossible. IIRC there was a Dennis The Menace game didn’t have the final boss ready for the publishing deadline so they just put an impossible jump just before it so players couldn’t get that far.

I’ve started to hate the term “Hardest”.

Give me two months in Unity, and I can make a game that’s “harder” than every game on any one of these lists. It would also be unplayable trash, that would prompt hundreds of “How the fuck are you supposed to XXX” responses due to obscurity. Part of what makes those listed games enjoyable is having a decent difficulty curve, compelling progression of skill demonstration, and a good feeling of reward. They’re getting difficulty right.

I hate hard games nowadays, but when I was a kid I had a high tolerance for them because that’s pretty much all there was. I have a fondness for the Ghosts 'n Goblins series because it was part of my childhood, but I wouldn’t give it the time of day if they came out now.

Elden Ring isn’t even the most difficult soulsborne game, by a longshot

Did anyone ever play Pursuit Force on the PSP?

That game was brutally difficult.