I think that line is just there to state the obvious that you can't say "security researcher" and get off free... your actions determine if you are acting as a researcher, not just a claim.
I don't find that the least bit weird.
I don't find that the least bit weird.
If I had just discovered a vulnerability, and didn't have a written contract authorizing me to do the research, I wouldn't feel the least bit of additional protection from this policy change, and would probably refrain from extorting the owner.
Edit: I had read "extorting" as "extolling" and associated with notification, not extortion. (I even typed "extorting" in this response.) I stand corrected, as extortion changes the tone of the qualification.