So why are people still afraid to talk, then? It's obvious that either the law isn't as crystal clear, the law does not prevent companies from writing FUD into employment contracts or that people are not educated well enough about their rights. Or: that they have economic pressure (e.g. no 3 months of savings, like way too many people have!) to stay in their job and thus cannot afford to lose it by ratting out illegal or immoral practices.
Now, if every company in the world had the legal requirement to add a paragraph like "in the event that you witness illegal behavior at the company, the law explicitly allows you to report such behavior to media, unions, NGOs and public offices, and we are required to pay you for the duration of the investigation", that would be a different story. Everyone who reads his/her contract would know it.
Tesla has a history of blaming the owners of their cars for accidents with plenty of people defending Tesla's actions. I would imagine that a paycheck-to-paycheck worker has to know that the response to them will be similar with the added bonus of a signed NDA.
Now, if every company in the world had the legal requirement to add a paragraph like "in the event that you witness illegal behavior at the company, the law explicitly allows you to report such behavior to media, unions, NGOs and public offices, and we are required to pay you for the duration of the investigation", that would be a different story. Everyone who reads his/her contract would know it.