I did the thing.
Diablo 3’s season 5 should be winding down within the next few weeks, so I finally got motivated to make the effort to unlock my extra stash tab. It definitely would not have been possible without the kind assistance of a few friends who helped me grind out paragon levels, legendary gems and gear. The reward of an extra stash tab was too much for a pack rat like me to pass up, but this process pushed me well past my comfort zone. Even after proving that I can in fact complete this level of content, I still believe that it was a mistake for a reward this desirable to be locked so far up the seasonal progression ladder. Stretching my meager skills to get this far felt like a chore and a relief when it was over, not like an accomplishment. Since I mainly enjoy playing solo it was also frustrating having to ask for help on some of the tasks. Among my more casual friends, many struggled just to complete the main seasonal journey and earn this season’s pet (mostly thanks to having to master a set dungeon). Locking cosmetic items like portrait frames and banners behind difficult content is one thing, but locking away huge quality of life boosts like extra storage space is baffling. I sincerely hope that when the season ends that extra tab will be obtainable some other, easier way, or at very least that next season’s stash tab is at a much more accessible point in the seasonal journey.
In any case, I’m happy to set D3 aside for a while now. Sure there’s one more tier of the seasonal journey left but I have zero desire to complete it, especially since it requires leveling at least one more character (in hardcore mode no less). The timing of my D3 hiatus couldn’t be more perfect, since I can devote all my attention to WildStar’s new Destination Arcterra patch!
Moonshine Mansion 
Congrats on getting it done! I didn’t even bother. Partly because it didn’t sound fun at all and partly out of principle. To me, this stunk exactly like the whole tedious Draenor flying achievement in WoW, where it felt more like the devs were punishing players for wanting something they really didn’t want to give out. Requiring some rather hardcore play for a stash tab is really ridiculous and the fact that it’s going to be a thing in every season is even more frustrating. I play a pretty non-trivial amount of D3, but things like leveling 3 legendary gems to 65 requires way more time than I’m willing to commit to one game. That’s a TON of GRifts. I’ve been working on my monk’s gear a lot, but he’s nowhere near capable of soloing a level 70 GRift. Then there are those Conquests…
Nearly everyone I know who completed it has said exactly the same thing about it as you, Grace. That they’re done with D3 for a while. Probably not the effect Blizz was going for.
Your reaction seems rational and pretty common. I am keeping my fingers crossed that it will be easier next season. I think these requirements were way worse than the Draenor flying achievement just in terms of general accessibility. Flying was painfully boring to get but it wasn’t vastly out of reach for casual players at least.