Unfortunately it's well established that accessing resources that, even if not protected what so ever, without permission is illegal. YT's policy T&S on how and when you can consume it satisfies this.

I believe in the youtube-dl case allowing you to consume videos outside of the T&S is the crime and the automated scale is the punative factor.

IANAL and I don't agree with this; just responding to the parent statement of "You can't circumvent measures that don't exist"