The worst part too about the Paladin quests is it's Heavensward that's most egregious. It honestly feels like someone had no idea what was going on, or didn't care, or left, and their colleagues left holding the bag with this mess of a story had no idea what to do with it.
ARR Gladiator quests are fine! They're along the lines of the other Class quests, intro you to the job and a complicated character dynamic, and it's a decent time.
The ARR Paladin quests...are just boring. They aren't actually even that bad, they're just...utterly predictable, bog-standard tropes and plot line where you can see everything coming malms away. But they have an internal logic to them that builds on the politics and scheming in Ul'dah. Jenlyns realizes he's an unwitting pawn of the Syndicate, and he was literally chosen for the job cuz he could be easily duped and controlled. He doesn't even get to have imposter syndrome, he's actually unfit for the job (and then strives to do better, leveraging support from Papashan and Mylla to shore up his own weaknesses, which is admirable!).
...Nevermind that traditional Paladins in general are a bad fit for Ul'dah. The heavily armored Sultansworn makes no sense in that desert environment, and looking at a world map we can even see that Southern Thanalan seems to be on the equator. Like it's not even a case of "it's cooler than it seems cuz they're further north." Because they're not. And I know the devs wanted to have Ishgard perhaps be a starter city but that was scrapped due to time and resources, fine but um.
Dragoons are still trained in Coerthas, by Coerthans. Why didn't they just...do that with Paladins? Keep Gladiator in Ul'dah, where it makes sense as presented. But then have to work with Temple Knights to get the Job. Especially since after Ul'dah's intro, the game just forgets the Sultansworn exist and they have no bearing on the MSQ the way the other factions in Ul'dah do. Not even in the finale of ARR's arc where it would make sense. Gladiators are a constant in other side quests and MSQ both.
Stormblood Paladin is also fine--because it goes back to those Gladiators, and we interact with Paladins and Knights across the realm, and deal with those complicated relationships between the Gladiator guild core members. It's internally logical in its drama about finally restoring Aldis's reputation and place in Ul'dah, against the backdrop of the tournament.
Heavensward Paladin straight up makes no sense. Solkzaygl's actions are entirely contradictory to his character and arc from ARR. There's no way for some of the actions to occur without him working with the outlaws in some way. Instead of teaching Constaint, he sends him on a merry chase across Coerthas to learn on his own, and it's only the WoL's aid that sees the boy live, let alone make progress. A random man dies, guilt-ridden, due to Solk's scheming and lies he confided to this poor guy.
And then Highlander-esque "there can be only one" nonsense. Even as a Highlander fangirl in my youth, it was insulting and awful. Papashan, Jenlyns, and Constaint all call out how nonsense, illogical, unlikely, and stupid this whole story is...all to make a sword shine.
Because there's no internal logic to events, let alone the reason for the string of happenstance that leads to the finale.
And we know it's possible; HW Blacksmith gives us a fantastic paladin story! One that fits Ishgard's storyline and HW's themes. HW Dark Knight is also a good paladin story, actually, as they are meant to be another angle on the concept of dedicated knight defenders. Samurai for the Eastern equivalent, and the concepts and tropes present in those quest chains.
But the job actually bearing the name "Paladin" is left in the dirt. As a fan of the concept across various games (video and TTRPGs both), it's quite frustrating how the devs had no idea what to do with this job, despite other members of the writing and scenario team presenting stories that would have fit perfectly well within the framework. Only some of it is misplacing where Paladins originate in the setting; the rest is not taking advantage of the themes and setting of the expansions, and just not caring enough about the characters and story to even try, compared to the rest. Or worse, they did try, and meant for more, but whatever intrigue and complex plot they wanted to create was too much for 5 quests and no guarantee the arc would continue in the future, even if it had landed perfectly.