Dungeons are not needed. Lore in them is not needed. Raids are not needed.
There are (well were) millions of people who played wow and never did any dungeons and raids. Ther are people playing wow now and they are not doing any dungeons and raids at all. Because those are not core features they are optional.
But it seems that the free game design lecture by me went over your head.
No you can't remove mining from minecraft and still call it minecraft. It would be a completely different game. Because mining is one of the cores of minecraft (the other core being crafting). The entire idea behind the game is to mine stuff and make stuff out of it. Mine fucking Craft.