There's nothing wrong with debunking something. It's just being skeptical about what you hear and trying to see both sides of something and finding where the truth lies inside that.

But the problem is the left misuses the term, much like their other favorite new term "gaslighting". Their version of debunking is having snopes or politifact (or some other far left outfit) take a valid claim, add some outlandish statement to it, then say that the outlandish part they added is false, therefore the entire statement is false, knowing damn well the majority of lazy idiots will only look at the result and not read the details.

For example: "Project Veritas claims Planned Parenthood sells mutilated fetus parts (true) to secret Satanic cults (unverifiable)." They would then say "untrue" because they can't find any secret Satanic cults that buy from Planned Parenthood. Morons would say "See? The claim that Planned Parenthood sells baby parts is untrue!" And then from then on out, any time Project Veritas is brought up, the media will say "Project Veritas, who has been debunked by Snopes, claims [...]"