This is false. I'm friends with many people across many companies, and we all openly share salary information, including RSUs. The numbers are fairly close, there's no way it's off by half. The biggest difference is Netflix, I would have expected them to be higher. Their biggest difference is they pay cash, and the culture is either you fit in and are extremely happy, or you're terrified of getting fired and you are within less than 6 months.

This is the biggest difference between now and 15-20 years ago. Before it used to be a secret but now everyone shares the data.