while harder difficulties turn enemies into sponges that absolutely destroy you in 1 or 2 hits.

Sounds like a normal dark souls experience to me, I see no issue

A. The game is actually art and the artist vision includes an option making it playable for more people

B. The game is a product that they want to sell to more people, adding difficulties sells more

I don’t see the issue either way. Why care what audience it’s conforming to, you’ll either enjoy the game or you won’t?