The taste isn't diminished THAT much by cold unless you're serving it ice cold. (colder than fridge temperature).
You may taste more of warm beer, but for some (including me) this is outweighed by the fact that it's warm. I find near room-temperature drinks (or food) of any kind pretty gross. It feels like drinking from a still swamp. Ugh. It's got nothing to do with the taste.
The same observation about 'warm' beer can probably be made about anything. Probably room-temperature sorbet has more taste than frozen sorbet, but wtf wants to eat that?
In summary, eating/drinking is enjoyable not merely because of "taste", but also because of touch (texture) and temperature.