While the exact numbers are unknown, it is true that there's a certain amount of people that either believe this nonsense and/or don't know why it is false.
This is the problem, because every bullshit creates a divide & conquer effect.
There will always be dumb people to believe the biggest lies. So if they keep pushing many lies one after another, we lose more an more people, and they could attempt a shady takeover like the bitcoin classic was.
If they gain enough support for that, then it could pose a serious risk to bitcoin after that.