I think that playing the same type of game twice through has already trained most people how to play the third, to the point where concerns about "accessibility" in Dark Souls II shouldn't really mean much to series fans.
As I was playing Demons Souls and exploring the last of the levels, all I could think about was how much I wanted more of exactly this experience, more of exactly the same game, just more levels. To a certain extent that's exactly what I got with Dark Souls. Nothing much about the core gameplay changed, only stuff on the periphery like covenants and humanity. I started Dark Souls already knowing I needed to get a shield that blocked 100% of physical attacks, that I needed to keep that shield up any time I was headed somewhere unknown, and that I needed to control each encounter as much as possible by pulling single enemies from afar and then managing my stamina. Plus a whole bunch of stuff like encumbrance, ripostes, backstabs, upgrading weapons, and damage types were similar enough to Demons Souls that I was able to grasp the changes pretty quickly.
So that fish-out-of-water struggle to figure out how to even play Demons Souls was already absent for me in Dark Souls. I'm just guessing (the same as everyone else) but when From talks about seeking to make the game more directly accessible, they could be talking about making sure everyone who starts up Dark Souls II has a better shot at learning the basics of how to play the game. It could just be giving new players the same base knowledge as people who played the first two games, and then setting them loose on the actual challenges of Dark Souls II.
