Nah, Diablo 4 is much more fun when leveling from 1 to 70 or so. 70 - 100 is just doing the same things over and over with barely any rewards. It’s the other way around there, leveling is fun, endgame is dogshit.
Usually “game starts at max level” is used for MMOs like WoW. Where all the leveling is seen as annoying bullshit fetch quests and at max level you do dungeons and raids.
I honestly don’t care about the story that much in games. A good story is nice, if the gameplay is there. If the only thing that is actually good about the game is the story… I’ll just read a book instead.