Okay so, I agree that developers should strive to add more difficulty settings so players can tweak their own gameplay experiences to suit them, whether that be a easier experience, a difficult experience, or even any level of difficult but just with added convenience options. It is all dependent on the player and personally I feel the method of just having "Easy, medium or hard" difficulty settings alone are sort of outdated, by themselves. While this method might work for the majority, I often feel with certain games (For example bethesda games) that the difficulty setting never feel quite right, medium might not prove enough of an engaging challenge for me personally, but "hard" mode makes the game a chore with overly spongy enemies, etc.
That is why I am more in favour of individual difficulty values that the player can tweak themselves rather than just a set mode that cannot be tweaked by the player, that way it benefits everyone as players can individually tweak various values (differing from game to game) to craft their experience.
But ultimately, as kratox explained, this issue differs greatly from game to game due to the difference in gameplay mechanics, theme and of course developer intention. Thus, I would not agree with you point "They can add Easy Modes, it's as simple as making enemies easier to kill so your Gameplay is exactly the same" because as I previously explained, this would not necessarily fix the issue which is obviously a problem if we are talking about making games more inclusive and dropping the "elitism" which certainly exists in certain gaming communities. Which brings me to that:
I agree with you, we should drop the toxic elitism which attempts to make some people feel "superior" to others because they completed Dark Souls 3 with no deaths or whatever the hell. Just let others play the game how they want at their own pace, with or without help at their own behest.
However, a point I do not agree with you with is that the only point against "Easy modes" is that elitism. That straight up isn't true. I agree that it is a factor for some rather deluded players will through a hissyfit if anyone dares suggest that a certain game series should perhaps be tweaked, screaming that "that is the way the game is supposed to be!". But a major point you seem to be missing is on the developer side, that being developer intent. This ties into something else you said about that games are supposed to be "fun". Ultimately, a developer is creating a specific experience that is meant to invoke certain the feelings and reactions in the player. For example, satisfaction, challenge, horror, mystery, intrigue, curiosity, and even frustration. You can summarise these different feelings/reactions that will be tied to different games and genres as the game being "fun". But that is a subjective term, what is fun to me will likely be very different to what you find fun, and vice versa. And game developers cannot appeal to everyone's sense of "fun". That is why genres are formed, why different people have different tastes in games which they find interesting and engaging.
So, simply applying a blanket statement that developers should just add easy modes does not hold much water, as it will likely affect developer intention and it is not always in the interest of the developer to appeal to everyone, thus adding a "Easy mode" for certain games might never be in their interest.
And of course there is the point that kratox brought up, that being certain games are near impossible to make "easier" without changing the base mechanics. For a personal example to me, I suck at platforming games, for example Celeste and games like that. So, how do we make that easier? Well...we could make it so it does the platforming for me? But then what is the point of the game as I will not be developing the skills to platform well within the game. Or how about we change the level layout? But then, it wouldn't necessarily be easier, or harder, or more or less fun, it would just be different.
In the end, this debate of whether games should have an easy mode should, in my opinion, be taken on a case by case basis. As you never really get anywhere trying to apply this as a blanket rule across the whole of gaming.