I think Blizzard went into Battle For Azeroth with the goal of making equipment "more interesting". I think a secondary goal was for a player to be able to get to 80% power fairly quickly, but have it take much longer to go from 80% to 100%. To that end, Blizzard came up with Azerite armor and Corruption.
My evaluation of Azerite armor is colored by the fact that I play a Holy Paladin. Of all the specializations in the game, we probably benefited the most from Azerite armor. It gave us a completely new play-style, Glimmer, that worked really well with the Holy paladin archetype. Alternating Crusader Strike and Holy Shock melded both melee combat and large single-target heals. It was a very enjoyable play-style.
It was also a good high-end play-style. You played like a traditional healer while accumulating 3x Glimmer, and then got to switch to the new style, making it something to look forward too. So I think that in a lot of ways, Holy paladins got the best of the new equipment systems.
Playing Hades has also given me some insight into what Blizzard was trying to do. In Hades, each run plays out differently depending on what gods show up and what boons you get. You can influence things here and there, but at the end of the day you have to "roll with the punches". You get what you get and you try and make the best of it. Every experience is a bit unique that way.
I think Blizzard was attempting something similar with Azerite and Corruption. You get what you get, and you try to make the best of it. The problem of course, is that MMO players really do not like this. Especially when someone else is lucky enough to get the elements that the community has deemed the "best". We saw a similar issue with Legendaries in Legion.
With Corruption, Blizzard gave up on it quite quickly and turned the system into something to grind until you got 8x of whatever the best Corruption was. To be honest, I kind of liked Corruption before you could buy them. You got what you got, and erased worse Corruptions while keeping better Corruptions, all the while juggling your net Corruption.
I do wonder if there were things that Blizzard could have done to make Azerite/Corruption better, and reconcile players to "rolling with the punches". I think one major improvement would have been to not allow Azerite/Corruption to stack. With stacking, 3x of the best Azerite is much more powerful than a random selection of lesser Azerite powers. Same thing with Corruption.
But I don't know. I think that mixed secondary stats are the limits of what players will accept as "interesting equipment". Perhaps Blizzard would be better off just going with that, and then a stingier drop rate closer to Classic WoW. It would mean that character improvement would be steadier, with slower increases in item level, but no chasing of random powers.