Whilst this isn’t always the case for almost any media (it’s possible to do faithful adaptations of things like Peanuts and probably Little Women as it was in the past), it seems with superhero media the continuity’s often so convoluted that writers have no other choice but to take liberties with the source material. Practically and nearly impossible to get a faithful superhero adaptation these days.
It doesn’t necessarily help that a lot of superhero comics tend to change writers that in all likelihood there wouldn’t be much of a clear consensus over the characters’ actual personalities. It’s likely Disney and Star Wars have similar issues to some extent, but it’s still clear when you keep changing writers there’s not going to be a clear vision of the character’s personality or fate.
At any rate, usually the televised or cinematic adaptation’s often the most accessible interpretation of the same character or story. Moreso with superhero comics for reasons I said before. It doesn’t help that DC and Marvel seemingly treat superhero comics as if they’re research and development that it’s probably why we’re never going to get a faithful superhero adaptation.
To make matters worse, even if the comics are like the canonical version those in more accessible media adaptations are often the first things to come to mind for outsiders. I.e. it’s like if almost every non-comics medium makes Barbara Gordon Batgirl, it’s going to influence people’s ideas and preconceptions of her that it’s going to have a big say in the comics later on.
In fact superhero adaptations are practically more influential and successful than the source materials are. It’s parsimonious to say that both the Joaquin Phoenix and Heath Ledger takes on the Joker more or less influence people’s preconceptions of him in recent memory. Likewise the Teen Titans programmes are far more accessible and popular than the comics are and will be.
So much so that the recent Titans programme’s practically based on the 2000s cartoon version. Logically the 1960s Batman programme more or less influences subsequent Batman productions. Anne Hathaway’s Catwoman’s obviously based on the Julie Newmarr version with Eartha Kitt’s take paving way for Halle Berry and a future Batman adaptation.
It’s safe to say that the telly and cinematic adaptations are far more influential than the comics are by sheer accessibility that it’s going to inform people’s preconceptions of such a character, unconsciously or not.