Have you tried recently? I don't remember the steps, but they let me create a public page for my YouTube account. I still have one Google/Google+ account, but all my YouTube stuff (videos, playlists, favorites, etc) is tied to that public page, which I've locked down on Google+.
So my channel still has my original YouTube name and comments won't be made with my real name.
Good luck. Google's adamant about using its position with search and YouTube and other products to get everyone to use Google+, and there's no room for anonymity on Google+.
"to get everyone to use Google+"
To which I say: good luck. :-)
My gamer tag youtube became a G+ Page that I can manage with my professional email.