When I joined Google I was very influenced by the 'Google is the good guy PR'. I never liked the Ads business model, but there a few Google products I really liked (Inbox, Maps and YT notably).
It's hard to pinpoint the wake up call, but I'd say it was project Maven (aka let's make an AI to help US drones kill more people), and all the lying and mislabeling there was around it (our AI don't kill people, etc…).
Wrt Cambridge Analytica, you have to go back to the mind state of 2016. At the time FB was mostly attacked because it was a walled garden hoarding all the precious data. So FB allowed users to share data with external apps. Then one apps managae to get data about 100k Americans and their friends and use it for helping Trump. And then 'data portability' was evil.