It's not about e-peens, it's not about gate-keeping, it's not about any of the things people seem to think it's about.
What it is about is changing the fundamental things about a specific game series that make that series special in the first place, the things that have attracted their particular audience to that game.
For example, how do you make Metroid more accessible? You take away the backtracking, make it easy to navigate and focus more on story sequences with easier combat mechanics to fit a more simple control scheme... which is how you got Metroid: Other M.
Now, while it is the most easily accessible game of the series, it is also the most hated among the people who play a Metroid game because they're fans of the Metroidvania genre. In order to facilitate the accessible features, the things that drew that audience to the game were sacrificed.
And as I said before, with Dark Souls, you can't just fudge a few numbers, cut down enemy health and damage numbers and bump up player health and damage numbers and it'll magically become an accessible game. To make it more accessible, you'd have to change a lot more about the game such as the way they environment is laid out so that people can easily map the level design in their head, or even provide a map for them to view to see where they are going.
Furthermore, you would need to change the multiplayer and messaging systems in the game to work with this easier mode since the map would have to be fundamentally different and advice given over the messages you'd leave would have to be restricted to the easy version of the game. You would also need to restrict the invasions so that people from the normal game can't invade an easy mode game, etc.
In fact, when you get right down to it, when you end up changing all the mechanics, simplifying the map and doing all the things you need to do to make the game much easier to play, you may as well just make it a separate game in the first place.
So in the end, there is a solution to this problem that everyone is overlooking.
Instead of trying to make a game more accessible to a wider audience, why not make a larger variety of different game series that cater to specific audiences?
I mean think about it. I simply cannot get into Dwarf Fortress... so should Dwarf Fortress change to cater to my needs despite the fact that I'm not good enough to play it? No, it shouldn't despite the fact that I'd love to be able to play it meaningfully.
Should Pillars of Eternity change the way it was made so that it's more modern and accessible and abandon the oldskool style Obsidian was going for?
I'm not a big fan of Fortnite and Apex Legends and don't think those games are for me in the slightest. Should I demand that those games change to cater to a wider audience that includes me? No, those games are fine with the audience they are aimed toward.
Since the last major Metroid game (Other M) was aimed at a wider audience, I am no longer a fan of the series. I still love all the games that came before it, but Other M threw me off and I'm kinda over the series now. It'd be nice for things to go back to the way they were, but if theoretically, Metroid Prime 4 comes out and it's aimed at that same "accessibly minded" crowd and is nothing like what a Metroidvania should be, then that's fine. Nintendo is clearly aiming for an audience that I am not a part of and I hope the people who enjoy Prime 4 have a good time with it... but I won't buy it because it's not made for me.
I don't expect every game to be accessible to me because every game isn't accessible to me. I have a very difficult time playing some games, maybe because they're too hard in terms of difficulty, maybe they're too hard because I don't understand the mechanics, maybe they're too hard because I can't grasp the nuances of the story.
But those games do cater to many people who are not me who are huge fans of those series and like them just the way they are.
And again, this isn't just about "adding an easy mode" this is about accessibility and how it affects the way a game is made and functions. For some series, this isn't a big deal, you can bump up and down a few numbers and people can have a pretty similar experience just with less health taken off per hit on easy mode.
In other cases, if you start messing around with numbers, you can end up breaking the mechanics of an entire game or worse. In the case of Dark Souls, where part of the story is meant to convey how brutally difficult life is for the poor bastards that inhabit that world, making things accessible takes away one of the key elements that is used to tell its story.
After all, video games aren't movies, over the many decades they have existed, developers have learned to tell a story via the players actions as well as other methods unique to this interactive medium.
Also, as I said, if it wasn't for the fact that Dark Souls is brutally difficult for most people, it wouldn't have marked its place on the map in the first place. Both Dark Souls and Demon's Souls before it would have been mostly ignored and we wouldn't have gotten its sequels, Bloodborne or Sekiro. Hell, for the most part Demon's Souls was ignored by a lot of people and it wasn't until Dark Souls and a stroke of luck that Dark Souls popularity took off.
If it wasn't for that, we'd never know about the cryptic story, lore and aesthetics that we would miss out on. But since FromSoftware has built its latest popularity on those kinds of brutally hard games, they're continuing that trend because they know who their primary audience is and are making games to target that audience who want more of those kinds of games.
I'm also no longer a teenager and am in my mid-30s, I care about having fun in games more than anything else too... and to that end, I also understand that people don't want their fun taken away either.
I keep saying it and I'll say it again: For some games, adding accessibility options such as easier modes works and would be beneficial to attract a larger audience, for others it does not and would only serve to unravel what makes that game special.