The point of my phrase is that perhaps Paladins, by being good and moral paragons, will like happy families - that is families that are not dysfunctional - will tend to have a certain similarity to them, whereas highly dysfunctional characters will like unhappy families all tend to be dysfunctional in their own ways.
From my perspective, the challenge of playing a Paladin is not in finding some sort of meaningful character arc full of character growth which might be the traditional way to conceive of a character, because you begin play as a paragon who is fully emotionally, spiritually, and morally mature. The challenge instead is to pull off that standing as a moral paragon in a way that is actually believable and leaves the character standing as heroic and admirable despite the challenges of being heroic and admirable in a world where quite frequently there is not an obvious way forward or way to go.
Pulling off characters like that is exceptionally hard - far harder than pulling off characters that are deeply compromised and dysfunctional and far harder than pulling off a character that is clothed only in self-righteousness that masks flaws in their character that are obvious to everyone but themselves. And as such, those presentations are extremely valuable, and extremely satisfying when they are done well, because they stand out more from the run of the mill characters.
A good approximation of this can be found in the character of Steve Rogers as presented in the Marvel Cinematic Universe. This is a Paragon character who manages to not fall into any of the easy traps for how such a character is presented, and yet within universe not only manages to maintain something like his integrity but is believably seen by even people who disagree with him as someone who is maintaining his integrity and therefore retains their respect - and to a large extent I think the audiences respect.
If you think that is easier to pull off than pulling off a character arc where someone comes to some realization and repairs their moral integrity, then I suggest you haven't done much writing. Steve Rogers was an incredibly well written character, and Chris Evans acted that challenging to inhabit character extremely well.
The real "Paladin Trap" I've seen more often in my years of gaming is to not even really try to aim at that high mark, or if trying to fail in hitting it utterly.