Uhh… you have to grind rep to access the main story.
You have to grind artifact power to get access to some traits and abilities.
You have to grind various content for essences to have equal abilities with other players of max level.
You have to grind rep to access flying.
You have to grind PvE gear to PvP at a high level.
I don’t know if classic will be a success or not, but some aspects of it have a lot of appeal over current WoW. If they re-released TBC/WoTLK/Cata, I’d definitely play those over current WoW.
The difference between old wow and current wow regarding the grind is that most of the grinds back in the day were optional, and you could do them when and how you wanted- there wasn’t basic gameplay locked behind them, and they weren’t time gated.
The only “required” grinds were raid attunements, which were only somewhat intensive in vanilla - in BC, they were toned down significantly, and in WoTLK, they were pretty much removed entirely.
Certain content/gear/crafting rewards were locked behind grinds, but since the power gap between player characters was much smaller (Ex: in vanilla, Naxx DPS isn’t even double MC DPS - that’s pre-raid BiS to pre-Naxx BiS), so while there was an edge to be gained, they weren’t as much of a necessity as now. And, the rewards from the most intensive grinds were usually cosmetic rewards like mounts or companion pets.
Back in Vanilla-WoTLK, rep grinds were optional, and there were multiple ways to complete them - dungeons, killing mobs, doing dailies, etc… You could take them mostly at your own pace/method, or skip them entirely. In current wow, pretty much all of the rep grinds are mandatory just to have full gameplay access.
It’s not. the Problem is when the grind is made a requirement for gameplay and time gated - like pathfinder and artifact power.
In old wow, most of the grinding was for materials, gold, experience (while leveling), gear, or consumables - most of which can also be bought/sold between players using the auction house, making what players grind and when a choice.
Gating abilities/traits (essences, artifact power traits), and flying (a gameplay/travel mechanic), behind the grind makes it effectively mandatory. You don’t really get to make the choice of when and what to grind or for how long anymore, especially with the severe diminishing returns due to the most efficient (and often the only) content for grinding being gated weekly/daily. Granted, that’s a necessity with the AP system, because otherwise character power differences would get even more out of control, and we’re already seeing player character power double (or more) in every patch, which is already absurd. With professions not being as relevant in BFA, farming mats also doesn’t have much value.