Except that at least Diablo 1+2 were for everyone. I remember playing those for the story and the gameplay. The loot and levelling were a means to an end for me - finishing the game.

The whole repeating the game again on harder difficulties, requiring better loot and grinding was very much an added bonus.

Diablo 3 decided to throw those who were there for the gameplay and story out the window, and was purely targeted at the grind. I finished the game in 2 days and still had half my characters skills left to unlock. What kind of RPG is that?

The Action RPG genre used to be about more than JUST loot grinding. It used to be about so much more, that welcomed players who were looking for all sorts from the game. Some people liked fast twitchy action mechanics, some liked the RPG story elements, some liked endlessly tweaking character builds and some liked loot grinding. But Diablo 3 is almost entirely focused on the last, with little room for the rest.