These days it seems hip to say "Steel is Real," but I'm not a big fan of this phrase. Carbon fiber, Aluminum, and Titanium are also real, of course, but the intended meaning is that the "feel" of riding a bike with a steel frame is better than the feel of riding frames made of other materials.
Most of the people who say "steel is real" are either riding 25 year old crappy ten speeds with gaspipe tubing, or modern steel frames made with thin walled but larger diameter tubes. Neither of these classes of bikes have the "steel is real" feel. Personally, I ride a 25 year old mid-range ten speed with high end gaspipe tubing, which is to say, not a bike with a "steel is real" feel. In fact I'm not sure I've ever ridden one of those bikes. Maybe it would be great, but would it be worth the money to find out?
That said, I do still prefer steel frames. I had a lot of fun browsing Busted Carbon, a blog dedicated to images of broken carbon fiber bike frames and parts. Reading that site provides one reason why I prefer steel.
It's not because carbon fiber fails and steel doesn't. Steel doesn't handle running into walls any better than carbon fiber does (though apparently it lasts longer if you tip your bike over in the living room.) The difference is how steel fails. You won't find any pictures of bent carbon fiber parts on that blog, because carbon fiber doesn't bend. If you're lucky, you'll find a hairline crack before it's too late. More likely, a part will suddenly and catastrophically fail and cause a crash.
Aluminum and titanium also break more quickly than steel once they become fatigued. I'm not against riding an aluminum bike in theory. My main problem with aluminum frames is that they're ugly. Actually, so are carbon fiber frames, but that's not my primary motive with those.
13 minutes ago