The biggest problem for most new players, including TheLazyPeon in his past attempt, is the 2.0 - 2.5 ARR slog. Past WoW friends I tried to introduce to the game couldn't get past how boring that was, and even when they get to Heavensward, they're already burnt out from all the cutscenes/dialogue. The regular ARR main story, while dull, goes by quickly, and your character is progressing throughout in levels, abilities, etc. Even WoW veterans can grind through it. But the 80 quests that are required post-ARR is the biggest roadblock, since there is zero progression, and you're literally just teleporting from location to location to get through dialogue/cutscenes. SE honestly did not trim enough fat here.

Those who argue it lays the foundation and is necessary for world-building really oversell it. Things like Good King Moogle Mog, Leviathan/Ramuh, the Ivy's subterfuge etc. could all have been on the chopping block (ie. moved to sidequests), without much loss to the primary narrative. They could easily just trim it down to the Monetarists subplot, the Doma refugees/Yugiri's arrival and Alphi establishing the Crystal Braves, and move right on to Lady Iceheart and Moenbryda's arrival. Hell, even the Monetarists, while critical for 2.55's conclusion, is basically a footnote for the rest of the game, so even that's scrapped in later expansions. Unlike later expansions where the post-HW, post-SB, and post-ShB quests continue the narrative from x.0 - x.3, and have their big moments...ARR's 2.0 - 2.3 is the definition of filler content.