In account settings, there used to be a link to be able to do this, but I don't see it. Is it no longer possible to do this?
Not sure what you mean? Google put all the services together under one account now, so if you login with the same account to both they're connected. But if you mean not to show the posts, I believe it is in privacy post settings.
It is actually, I did it. You can just delete Google+ by going to Google settings within your YouTube account. Worked for me.
Yes I did it just the other day. I don't use G+ at all so I am happy to delete it. In YouTube, click on your profile tab at the top right of the screen. Then click on your email address at the top. This will take you to Google Settings. Under the Account Preferences section, click on Delete your account or services, Delete products, and there you can delete G+ from your account.
I believe that the address is myaccount.google.com - I had absolutely no idea it can be done this way. I apologize for my previous answer.
Yes, that's correct. It doesn't just disconnect G+ from your YouTube account, it deletes it from all your Google linked accounts.