I played around with google account options yesterday (because that's what I do on my saturday nights ). Seems like the problem is that youtube accounts are now "managed" through google+ by your google+ profile. There's no way to make the youtube account independent, because even if you delete your google+ profile it just transfers ownership of the google+ youtube account to your email, and manages the regular youtube account through it, and you still have two accounts on the account switcher.
Deleting your google+ profile does solve the problem of having two channels capable of uploading though, and it doesn't seem to load the unwanted account by default anymore, since it no longer has any channel connected to it, but I dunno, it's only been a few hours since I did it.
If anyone else wants to try: https://plus.google.com/downgrade/ (Except I'm not sure that's the link because it redirects me now that I don't have a google account. I think the option was under advanced settings on youtube, if that's not the right link. http://www.youtube.c...ccount_advanced (again I'm not sure because the option doesn't show up for me anymore.))
And, as a bonus, here's youtube's answer to all of our problems: https://support.goog...f_topic=3254256
What if I don't want to use google+
Many people use YouTube without a public YouTube identity (a YouTube channel). For example, if you just want to watch, like, and subscribe, you don’t need a channel. And if you don’t have a channel, you don't need to have Google+. See Do I need a YouTube channel? above.
If you do choose to create a YouTube channel, your channel needs to be connected to a Google+ profile or page. This will have your channel’s public name on it; it doesn’t need much else. It’s up to you to decide how much information to put on the profile or page, and how much (if at all) to engage on Google+.
If you don't post on Google+, your profile or page will show the YouTube tab by default, where people can find thumbnails of your videos and a link to your channel. If you want to limit discoverability of your page or profile, you can hide it from searches.
e: And today I found out that you eventually revert to having the same problem Moth has, except now that there's no youtube channel associated with your profile (except the
fully functional and familiar deprecated one) you can't make playlists or favorite videos or add them to your watch later playlist or do anything involving playlists or self expression until you use the account switcher at the top every single time you decide to use youtube.