When a company tells people to join open-source but their main products which make them money are not open-source. Google has over 2 billion lines of code, most of which are proprietary.

Is IBM watson, Unreal engine, iOS, Xcode, Visual studio , etc open source? yet these companies keep advising public sheep to "contribute to open-source".

Just Go on github and see that the vast majority (99%) of projects are low-effort garbage.