Point - Brian Acton (Co-Founder, Whatsapp): "They (Facebook) are good business people. They just represent a set of business practices, principles and ethics, and policies that I don’t necessarily agree with" https://www.forbes.com/sites/parmyolson/2018/09/26/exclusive-whatsapp-cofounder-brian-acton-gives-the-inside-story-on-deletefacebook-and-why-he-left-850-million-behind/
Counterpoint - David Marcus (VP Messaging, Facebook): The other side of the story - "attacking the people that made you a billionaire is a whole new standard of low-class" https://www.facebook.com/notes/david-marcus/the-other-side-of-the-story/10157815319244148/
The main lesson - "Don't sell your company if you don't agree with your buyers' policies." Whatsapp sold their company for a huge profit to an ad platform. What did they expect?
Now he’s talking publicly for the first time. Under pressure from Mark Zuckerberg and Sheryl Sandberg to monetize WhatsApp, he pushed back as Facebook questioned the encryption he'd helped build and laid the groundwork to show targeted ads and facilitate commercial messaging. Acton also walked away from Facebook a year before his final tranche of stock grants vested.