That's where we differ in. Once you get the six set pieces, which is comically easy, you immediately jump to T8-10. After you get the rest of the items and finish the season challenges, you're basically done with the season. There's nothing else hugely rewarding unless you really want to go for the ladder, which is a huge time sink because of the various mechanics in place, cheaters and lack of trading. The only thing that is keeping the game alive are the patch updates.
I'm willing to bet that when they stop patching it and the next game comes out, it won't be played as much as D2 today because of the simple fact D2 is more social. Progressing through D2 actually feels natural as opposed to D3 where 1-69 is basically a stopgap until the real game. That's bullshit game design. Paragon levels are bullshit because every level after 800 increases your main stat. Everything before that, it increases such desired stats as max resource, life regen and gold find. Bounties are bullshit because instead of playing in groups, you split the group to maximize efficiency. Greater rifts are bullshit because of the importance of mob density, pylons and type of rift guardian. Ancients are bullshit because of the lack of trading and the randomness. Augmentation is bullshit because of the monumental requirements to gain more mainstat.
D3's endgame is bullshit.
You can't be fucking serious with this nonsense.
D2's endgame is farming fucking Baal over and over. or turning all your duped SoJs in to a vendor to try and spawn Uber Diablo, if they haven't changed it my endgame experience consisted of seeing what IP address I was connected to and hopping servers to find the one that was nearing the SOJ turnin limit, based on forum posts where people would relay such information. Frankly, if they have changed that (wouldn't surprise me), it's a little late don't you think?
DIABLO TWO HAS NO ENDGAME. It's just farming piss easy mobs for eternity until you get bored and quit for a few years.
It's comical that you mention that you can solo shit in D3, as if you are ever 'encouraged' to group in D2. Group rifting in D3 is a very popular and fun activity, synergies between classes are much much much stronger than in D2. Heck, in D2 I would be weaker playing with most players than I would be with Waheed my trusty Act 2 hireling. Diablo 2 is the game that literally has a chat command to simulate having more players in the game just so that you can bump the xp gain without having to interact with anyone else. Yes, it also makes the mobs harder, which doesn't matter because they die incredibly quickly and have no chance of killing you regardless outside of some pure bullshit combinations of affixes depending on your build. (Speaking of, y'know the most bullshit affixes in D3? Yeah they actually took them out instead of just leaving bullshit in the game, smart decision. Every affix has SOME amount of gameplay related to it, instead of "Immune" or "attacks and runs too fast for you to react" like D2)
Literally everything you claim is 'bullshit' in D3 doesn't even have a fucking equivilent in D2, D2 has nothing of any challenge. Gearing/progression is a steady slope because gear sucks for the most part and you don't need to ever become more powerful because the game never gets hard. The more I think about it the more laughable your argument is. "Once you have all the items you want you're done with the season" ....k? Maybe YOU are, many people keep going. I have put ~100 hours into each season to complete the journey and I'm not even close to maxxed out in any sense of the word. I'm happy with that amount of time. I mean, what a bullshit statement. Yeah, once you get everything you want to get you are done. Apply that to literally every game that has ever existed. I can arbitrarily decide when to stop in Diablo 2 as well, but it would certainly be easier to attain a shitty verison of you optimal layout in that game, does that mean you'd be done even sooner? They also don't add new shit every season there, so by that logic there hasn't been a reason to play the game in YEARS (hint, there hasn't for the most part).
EDIT: In case anyone is getting the wrong idea, I *LOVE* Diablo 2, it's one of my favorite games of all time. I still have the CE box proudly atop all my others. My point has nothing to do with thinking Diablo 2 is a bad game, it has to do with objectively analyzing what people are very clearly unable to do themselves, which is why Diablo 3 isn't shit and why Diablo 2 is best left in the past in comparison.