I wouldn't suggest you listen to them blindly, but you're crazy if you think YouTube didn't ask actual attorneys for a risk assessment (their VCs would have required that). They certainly didn't ask a bunch of hackers.
insert JP Morgan quote
For those who've never heard of this gem :)
Well, I don't know as I want a lawyer to tell me what I cannot do. I hire him to tell how to do what I want to do.
~ J. P. Morgan