The meat of this game always has been endgame. The endgame is mostly group content. You’re not ever going to get as much single player content as there will be group content. You’re going to have to accept this.
Blizzard didn’t make everyone stop playing there, go level something somewhere else.
This is a lie.
As has always been since the dawn of the game.
It’s not impossible.
Stop using words that you don’t know the meaning of.