All of the Dark Souls games, including Elden Ring, are what is called "challenging". But not challenging in the sense that a Times crossword puzzle or an university exam is challenging. Rather, for these type of games, challenging describes the necessity to learn what moves a boss mob is doing, and then be able to precisely press buttons on your controller with the exactly right timing following certain signals about impending attacks. So there is at least a part that requires "learning", but even perfect learning wouldn't help you much if you couldn't get the timing of the button presses executed right.

I was never any good at timing button presses right. And as I am approaching retirement, my reaction times are significantly slower than those of the teenage / young adult average customer for a game like Elden Ring. I would simply fail a lot more than most other players, and most likely get stuck at some point, presumably already the first boss mob.

I do believe that "challenge" in general can be fun. The idea that challenge is fun was pretty widespread in game development circles, until idle games and the like demonstrated that some people also like games that have absolutely no challenge at all. But at least a solid portion of the gaming population prefers to be challenged in some way by their games. However, different gamers find different things challenging in different ways. And the "fun" part of challenging games is to recognize that something is hard for you, and then ultimately to overcome the challenge and to feel good because you succeeded. If the challenge of a game is too hard, and you either never succeed, or it takes you bloody forever to make even the slightest progress, chances are that you won't find the game fun at all.

Given that a number of people likes games with little or no challenge, and that others like to be challenged at their personal performance level, but that performance simply isn't very high, many video games, and even some campaign board games, have different difficulty levels. Including "easy" or even "story" difficulty, designed to be playable by just about anyone. FromSoftware, makers of Elden Ring and the Souls series, apparently doesn't believe that a game should have variable difficulty. As a result, some customers, like me, will simply not buy their games. It's a bit like a "must be this tall to ride" sign in an amusement park, just on a reaction time scale instead of a height scale. I am simply not fast enough to play.