No.
100% false.
If that information is key to the nature and success of a product, then it's called 'know how' and it's both legally and rationally protectable.
You people need to grow up and grasp that fact that once you go to a company and they teach you what they have spent $100 Million dollars on developing, that you cannot walk across the street and spill the beans on 80% of the materiality of that R&D which happens to be such details.
All you care about is the profitability of the company, and you think forcing employees to sign away their ability to work in their field is an acceptable solution.
People are getting hired for 3-month contracts and then getting sued when they find a similar job a year later. People are getting laid off and then getting sued by the companies that laid them off for getting a job at a competitor.
Fuck that. The job market needs competition, not a focus on raw profits above all else.
If your employee leaves your company, joins your competitor, and then leaks your trade secrets, then sue them for that. Don't sue them for even getting a job at your competitor - that doesn't mean that they are leaking secrets.
And if you think that your employees are so untrustworthy that getting hired by a competitor is a guaranteed leak of trade secrets, then that probably explains why you are so terrified that they will leave you to find a new job. You're a terrible employer, and they would be better off with a different job.
But let's face it, you don't have any employees, because you aren't an employer. You're a "temporarily embarrassed" entrepreneur who is already convinced that someone will try to steal that million-dollar idea you haven't had yet. Well, I wouldn't work for you, nor should anyone else, so good luck with that idea once you have it.
That said, it doesn't mean that it's either ethical or necessarily legal for them to go to company Y and immediately do a core dump of every marketing campaign they ran and what the results were. But there's a fuzzy line between doing that and saying "Oh, millennials really respond well to this sort of language, but be careful not to say this."