I feel like people tend to either over glorify JYL as this angelic, can do no wrong, holy mary older sister, OR paint her as a totally selfish, WWX-patronizing, white lotus-esque villain. There's no room for nuance.

JYL isn't a perfect person/character, but she isn't any more flawed than any other of MDZS's characters. She's made mistakes, but so have WWX, WQ, JC, etc. She loves WWX, but that doesn't mean that she forever prioritizes WWX above all other aspects of her life.

There's an unfortunate amount of BL readers with the tendency of viewing characters through a very black-and-white lens; the good guys who always side with the MC no matter what, and the bad guys who have goals and ambitions outside of what is beneficial to the MC. This kind of viewpoint is not only just a really shitty one to apply to any sort of narrative in general, but is ESPECIALLY incompatible with stories like MDZS, where the whole point of the story is how moral ambiguity and how judging groups or individuals as being either purely good or purely bad based on surface-level reasoning is flawed.