People often lie not only to others, but also to themselves. Also I don't see a problem with somewhat controversial takes from anonymous accounts; given today's internet opposite would be brave/stupid.
Is it that you morally disagree (I agree that it is a poor reward for doing me a service) or you have a disagreement about why society punishes whistleblowers?
I disagree with equating whistleblowering and snitching. We all have dirty secrets, but let's loosely say that the scale matters.
It is a different story when coworker tells "boss" who is lazying around, and a different story when someone reports a serious misconduct towards other people. I'm not sure how to phrase it clearly, but generally I would not associate myself with former people, but I wouldn't mind the latter. Maybe one day they'd prevent me from doing something really terrible (given I wouldn't know better).
Possibly a fundamentally different outlook? I would trust a whistleblower, but I would have difficulty trusting a person who would cover up serious crimes for an employer. Most employers, by the way, actually do not want it covered up when one of their departments is Doing Crime.
(In particular if you're in, say, finance, or a safety-critical industry, you are not going to want to hire someone who has a known track record of failing to report crimes. I mean, unless you're, like, FTX or someone.)