I can't stand the taste of warm beer (i like to assume i'm not alone), and will turn it down if presented. Perhaps it's because i'm accustomed to it.
Did people used to enjoy drinking warm beer?
My money says you're a Yank.
I'm also puzzled by this idea that "beer" all has one taste, but maybe the few brands in your neck of the woods do.
People always enjoyed drinking unchilled beer, or they couldn't have drunk beer. Many people around the world still prefer room temperature beer - say, the British. Chilled beer has less flavour, which in the case of a number of US beers greatly improves them. They do taste nasty unchilled. (Recent reading of WW2 guides to European countries for GIs.)
People, in cold weather, might enjoy hot beer. You pour beer or ale, perhaps with spices or other ingedients, into a tankard. Then you plunge in a red-hot poker from the grate to heat it. (Horizon History of Eating and Drinking and old recipe books).
Now, this doesn't mean beer left sitting in the sun in a bottle. You keep beer in kegs in a cellar.