I hated Diablo III when it first came out as much as the next guy... but I totally don't get all the hate here for the current game.
A. The game today is nothing at all like the AH garbage that launched. With RoS the game is amazing. The story was fun instead of a chore.
B. They just added all the new Legendaries without needing to do the season at all... and now you are whining that they still have content to be unlocked for the people playing the seasonal characters. ??
C. I don't disagree that 5 tabs is very limiting... not sure it is worth the hate though. Seasons are nice since everyone is starting fresh and you don't have to worry about some pimped out level 1200 paragon dude invading your game, or whining that you are only paragon 300 (at least for the first couple weeks).
Avoiding season 5 only because I did all there was to do in Season 4 and am taking a break for a bit. But if you have never tried a season journey, it was loads of fun...
I honestly only touched the story season 4 when I self twinked another Monk to 70 just for fun so I could have two equipment/skill chars without swapping everything for single player vs group. (Took like 40 minutes to get to level 70 with a few gem's of ease for healing armor and ancient set weapons, stayed in like Torment 6 for most of that until I first got killed around level 67 or so! I think I was level 63 or so before the lagging notifications of new skill slots and skills stopped.)