I think FromSoft's games (and specifically the ones directed by Miyazaki) will be among a small set of games released in the past 20 years that will still be played and studied in 50 or 100 years (or more).
Also, this statement from the article:
> Miyazaki has created the most difficult games of the century.
This is absolutely not true. There are many games that are much, much harder than Miyazaki's games. And it was definitely never his goal to make "the hardest games". The goal, from everything I've read about him, was to make difficult games where the difficulty reinforces the themes he wants to convey, and evokes the emotions he wants you to feel. I could name a bunch of games that are harder -- including Nioh, a game that's partially inspired by Dark Souls, and has a similar combat system (but with a lot more complexity). The difficulty is an important aspect of their design, but it's just one piece of the puzzle.
There's a quote from one of the characters in Dark Souls that I think gives a hint as to why Miyazaki makes hard games:
> The dragons shall never be forgotten… We knights fought valiantly, but for every one of them, we lost three score of our own. Exhilaration, pride, hatred, rage… The dragons teased out our dearest emotions… Thou will understand, one day. At thy twilight, old thoughts return, in great waves of nostalgia.