Reputation grinds: The rep doesn't go away. Your rewards for grinding that rep still exist and don't arbitrarily turn off because you switch zones.
Attunements: Several heroics and raids used to have keys. None of which required you to complete virtually the entire expansion worth of content to get. Pathfinder is objectively worse than any attunement.
Resist fights: Are you joking? A single encounter which you could obtain gear for in a matter of days vs an entire expansion worth of work with multiple rep requirements.
Vanilla PVP HWL grind: This is debatable. But since it was a PVP achievement that never got turned off, I don't think it's a fair comparison. You were competing against other players, not the game itself. I'd still call Pathfinder worse, considering that it rears its ugly head in two expansions, vs HWL grind being only a single season.
World bosses: Again, are you joking? A single encounter vs an entire expansion worth of work. No comparison.
Gates of AQ: Similar to the HWL grind, but I'll grant that this objective was a little ridiculous. However, I'd also point out that it was the entire server working together, and not an individual. And once completed was done. Many people gained the advantage of the gates being opened without every contributing anything. Whereas pathfinder still exists and must be done in order to fly, even though the expansion it is in is no longer current or relevant.
And anyway, the simple fact that you had to go to the dark age of Vanilla in order to find a system as bad or worse than Pathfinder proves my point more strongly than any words I might use.
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So basically all you're saying is: