I agree with the OP to an extent.
But what a lot of people are saying is that this is fantasy and that mitigates over-the-top armour. Honestly? It doesn't. It's like the difference between a functional, nice looking car and an SUV with monster truck tyres; one looks and IS functional, a pleasing aesthetic of its own, while the other is a hilariously over-compensatory abomination and an eyesore.
But other people are saying that realism will ruin their fantasy. I would like to point out that almost all fantasy is derived from myth and lore AND art of older cultures.
http://www.draconika.com/images/saint-george-dragon.jpg
http://russkiyimperatorskiydom.ru/picture/img/Janna.jpg
These suits of armor are worn by figures of myth and they look quite adequate as protection and ornate enough. The reason that realism (of a degree) is essential in any work is because once you have godly characters walking around wearing half a scrapyard, it becomes irrelevant; why should we care about an unstoppable juggernaut? How are we supposed to relate? I know that in most RPGs the goal is to create an idealized version of ourselves, but really.
Take a look at Lord of the Rings. That had excellent armour and character design, and Aragorn hardly ever wears full armour and Gandalf is a goddamn wizard. That whole story was about the physically weakest of all (the hobbits) triumphing in the face of insurmountable odds with the most meager of resources.
But finally, many people say that practical armour looks boring because it isn't detailed or ornate enough. may I present to thee, the Lion Armour.
http://www.youtube.com/watch?v=ZJMBRq_RnPk
Post Script: Fighting between two knights was not long and boring as some people seem to think; all of a knights weapons were capable of defeating armour, even their daggers, because they were trained on how to use them properly. And they were not slow or unwieldy in their suits. They were taught all their lives about speed and agility in armour, which took the form of a sort of medieval parkour in full plate.