Based on experiments I did years ago, most people have no idea what the taste difference is between beers. If you take away the label, and have them pick a beer they like based on flavor alone, most people are lost. I doubt it's changed any over the years.
The key words in your post are "years ago." In the last 10 years or so, the quality and number of craft brews in the US has gone through the roof. I know guys who were strict Coors Light drinkers who won't touch the stuff today. Beer drinkers I know often talk about what they're drinking the way that wine drinkers describe that beverage. It all depends on the sophistication of your palate. Heck some people like Barefoot wine. :)
Alan, I totally agree that there is a lot more variety in beer these days that there used to be, but I'm skeptical whether people can really discern all that they think they can. What I used to do was to take a number of beers and put them into unmarked glasses, and then let people sample them, and give their opinion. Certainly everyone could detect flavor difference, even back then, but which flavor was "good" and which was "cheap" or "nasty"? That was the hard part.
My experiments showed that back then, if they knew which was which, the heavily advertised beers were always "good", while the cheap ones were always "nasty", but if they were drinking from an unmarked glass, they were just as apt to choose the cheap one as their favorite. My personal favorite among lager beers was "Blatz" which was not only cheap, but I liked it. Furthermore, since flavor-wise it was virtually indistinguishable from Michelob, that allowed me to prank numerous people by putting them both in the same taste test. Hehe... fun times.