Here's an example: https://www.theverge.com/2016/6/2/11837566/elon-musk-one-ai-...
Read past the fluff and the skynet. He's telling us Google scares him and makes him concerned for democracy.
Very carefully. I mean, that's not much of an argument. Lots of stuff is successfully kept secret. The US managed to keep a lid on their surveilance for decades (iirc) before the lid got blown on that, and people used to give the same argument you are in that context, too.
What's the alternative? Do you think megacorps never keep illicit things under wraps for extended periods of time?
I guess you could use it in reverse and produce an upper limit on how many people could be involved in a conspiracy if you assume that it has been secret for five years.
That said, Elon Musk gives every impression of being a massive chatterbox who can’t keep his mouth shut even when its the SEC threatening to take Tesla away from him, so I very much doubt any conspiracy involves him.
[0] https://journals.plos.org/plosone/article?id=10.1371/journal...