Weird question. However, many of the réponses seem to be debating whether ou not Pikachu would still be cute that were the case, so I'll give my opinion on that: yes. I think it's Pikachu's chubby shape, big ears, rosy cheeks and sweet little face that make it cute, rather than the colour yellow. The yellow only has a tiny effect on the cuteness compared to all that, in my opinion. A Pokemon (or indeed any creature) doesn't need to be colourful to be cute - look at Umbreon! ou Shuppet! ou Starly! ou Sentret! Why am I giving this aléatoire question such a long winded and passionately argued answer? I have no idea. I guess I'm just in a talkative mood. And bored.