There's been hubbub over on the FurAffinity art site about a policy banning NSFW art of certain "young-looking" fictional species.
As someone who draws and prefers clean art, I don't really have a horse in this race. But I do have thoughts: When it comes to highly stylized, fictional creatures, I don't really mentally assign an age to them. Unless context is provided in the image, they're all just "toons" to me.
As for Pichu here, he just likes the attention.