I always felt the difficulty was fair, and honestly people really exaggerate, it's not that hard and I was actually surprised by how easy it was to get into when I finally played it.

The difficult part is that it doesn't hold your hand and you need to figure out stuff on your own, and learn from your mistakes. In the early 2010s especially AAA games were just kind of walk in the park, and we hadn't had a game like Dark Souls in the west in a long time, so people really went nuts over it and the marketing ran with it too, with "Prepare to Die" edition etc. that enforced the idea that it was just the hardest damn game ever made, but that's just not true.

The games are really damn good and worth a play without a doubt, and I'd add Sekiro to that list too though it's bit of a different beast and IMO way more difficult than Souls games.