As far as the privacy, there are a million things that people don't want public:
- criticizing someone
- disagreeing with a business plan (example, ABC company just got startup funding for an editable blockchain project -- if I think that's a bad idea I'm not likely to say so publicly because I don't want to harm them ...I'd rather talk to them and convince them)
- discussions of joint ventures or deals that are not public
- discussions of challenges (XYZ Funded company keeps losing key staff and thinks it's hurting the business badly, they want advice from fellow CEOs...they would not ask this publicly because they don't want to cause alarm or scare off customers)
- is _____ a scam?   Privately I will circulate names like I have concerns about ____ and here are the concerns -- I won't do so publicly unless it's like OneCoin and I'm 100% absolutely sure it's a scam.   If I'm only 90% sure I won't tweet it because I don't want the risk of slandering a good business

Etc.