You just nailed this in my opinion. As you have said, there are still thousands of YouTube's videos around the platform so, in my opinion, the videos they look out for are the ones that actually violated their terms and regulations and not just all the YouTube videos.

With your analysis, even a friend of mine has been creative about cryptocurrency videos on  YouTube and none of his videos got deleted. So, those videos targeting to scam gullible are likely to be deleted from the platform.