Apparently people are still writing articles about this??? But anyways I have wanted to talk about this but haven't had anywhere to say it.
From searching for this apparently my take isn't completely original either, but I think I cover more with it.
The Dark Souls series is designed well in many respects that just seem to go over people's heads if they don't think too hard about it. Like, you'd absolutely feel a difference if these things were different, and a number of bad "souls like" games that miss the point of certain design elements of the Souls games essentially prove that.
One of the things that people do without completely thinking about it that way, is setting their own level of difficulty. The game is pretty much designed so that you can win it under pretty much any circumstances, it's just that some things give you a much better margin of error. Most articles identified co-op phantoms as the easy mode, but I think that's just the start. Playing slowly and over leveling your character is also in a sense easy mode, though that depends on whether you think that or sticking to a specific pace for leveling is the normal option. I really should say Sorcery is also easy mode, god knows I've cheesed a ton with it. It's not like I've even sacrificed much melee fighting ability for it, either (thanks MLG sword). Way of the Blue is there to help if you are invaded (or more realistically to get summoned at the moment a comically oversized sword is being shoved into your back). I do believe that most people of fairly average skill or below average skill could beat the game using some combination of these.
There's also a large amount of hard options. Some of them are obvious and explicit like the Covenant of Champions in DS2. Others are more user defined like playing as a level 1 deprived and beating everyone to death with a ladle exclusively for the entire game. There's also caveats to this type of nonsense, like how armor is often not that helpful anyways compared to the amazing dodge rolls you get while unencumbered. So quite a few of the harder options give you benefits! (Also worth noting that DS3 inverts this somewhat, with how summoning two phantoms will nearly guarantee that you get invaded by multiple dark spirits) Not so much for the ladle though. Then there's also DS2's no death / no bonfire runs which reward unique rings.
There's a reason why the attitude you see in the community is that using co-op and other things cheapens the experience essentially. The most conventional way to gauge difficulty would generally involve making full use of every trick you have. Doing this would mean summoning phantoms for every area, always being 20-30 levels over the normal level for the area, using a build that doesn't require you to be anywhere near the enemy (basically have your phantoms take hits while you spam Soul Arrow), and looking up guides for every area so you don't get too surprised. At least for most of the existing player base, this would make things extremely easy to the point where it doesn't even feel very rewarding, so it shouldn't be a surprise that the community normalizes imposing difficulty constraints on yourself.
And of course, the most important part of this design element is how it helps you develop skill. If you play through again -- or even just do new game plus -- you will have learned things that you'll want to apply next time around, or you will otherwise want to impose some new challenge. I started out playing with a group of three players, but I eventually did move on to doing a solo playthrough once I had a build that I really liked down, and damn did it feel good to fight all the bosses one on one. Felt fairly easy by then, too. That's what it means to git gud -- play within your comfort zone, learn the mechanics, learn from your mistakes (the game is generally very good at making it apparent why you died and what you need to do to avoid dying again, something else bad souls likes often miss), and then move beyond that comfort zone. It doesn't necessarily mean level 1 ladle deprived blind playthrough or bust like some people seem to think.
Dark Souls handles it’s difficulty scaling extremely well and I hadn’t considered some of the factors going into that. Good write up.