Whistleblowers get destroyed in the culture we have right now, they loose everything. It don't think its reasonable to ask people to destroy their own lives so that we might one day find out about the horrors that companies do only to watch as nothing is done to resolve it with the perpetrators.
If the circumstances were different and the public didn't stand for such widespread mistreatment of those that stood against illegal activity then there is different advice, but far from having protections for whistleblowers as it stands we only have punishment.
Even internal-only whistleblowing on non-safety things like IP issues or quality can be risky.
In theory you are helping by making them aware non-publicly. But if profits are good they may want to keep these things quiet and unresolved.
With unemployment at ~4% unethical people just want to continue guzzling unethical money until snot hits the fan -- when product or service collapses under the weight of the problem then get a new job at same pay. They don't want to fix anything even if long-term its a big problem. OTOH, when employment is 9% then it isn't a sure bet that equivalent job is available, and scammers need to adapt faster.
I would say it depends on the context. Are you in a profession with an ethical obligation and an oath to the public like a doctor, engineer, or lawyer? Then I think you have an obligation to say something regardless of downside. Those aren't "jobs", they are "professions" because they profess an oath that should be more than mere words.
If the circumstances were different and the public didn't stand for such widespread mistreatment of those that stood against illegal activity then there is different advice, but far from having protections for whistleblowers as it stands we only have punishment.