That toolbar tho. Ugh. I assumed he was talking about Outlook.com, not Outlook 2013.
Ribbon is collapsible in all Microsoft applications: Ctrl+F1 or click on the ^ in the right most part of the ribbon.
Does the search folders work for RSS feeds too?
It does. The RSS feed items are treated like emails, so you can choose a feed folder or multiple folders and set up whatever search parameters you want. I set one up to show all articles posted by "ris," and it worked as you'd expect.
What's stopping you? No reason a mail client can't do RSS as well, is there? (I'm pretty sure some do, or at least did.)
Some do/did, indeed. I personally prefer Feedly, though.
Thunderbird supports RSS feed support, though they are kept separate from e-mail, somewhat.
Every good mail client does RSS, including T-bird and Outlook - but they don't sync subscriptions and read/unread posts to the cloud, so most power users prefer a Google Reader clone.