It should be expected everyone isn't going to like everything depending on the writer and subject matter. I feel this is more akin to thinking all of WoW is great because Wrath was or all of WoW is awful because WoD was. Neither are true, but it's acceptable that players would find one section more or less enjoyable than another. Just because FFXIV has a continuous storyline doesn't mean it's not applicable. Even in book or television series this is true with certain ones being praised or criticized more than others, so I don't find those comparisons apt especially as there were several series I did not like the introductions to that I grew to love later.
My main complaint about ARR was the superfluous dialog. There's even a line in an animated parody where one of the characters says, "You just summed up 30 quests in one sentence." Yep, that's ARR. I found the majority of the characters unlikable. Some of them vastly improved and are now among my favorites. I was not interested in the bulk of the subject matter, most of which changes or at least evolves to become interesting in subsequent expansions.
I did not like how my character was treated as a tool. Left to my own devices, I was given no reason to join the Scions. It was as if my character decided she had nothing better to do than be at their beck and call, which Alphinaud at least later admits to using us. This also changes substantially as you start to become viewed as a friend or family to those you interact with at length.
Once I got to HW, things improved dramatically. The problem is ARR is so long, it's a massive time sink to convince players to get through and there's no guarantee to be a payoff at the end if they turn out to not like HW. While the gameplay itself doesn't change, the characters and story certainly do. I would recommend not quitting ARR if you're liking everything else but those two things because they do get better (along with combat). I find saying that the whole game is like ARR factually incorrect as I would 100% buy a story skip if I had to do ARR again, but I would NG+ HW.