I totally agree that those functions of the visual system are features and not bugs, but I still think the analogy to biases holds; after all, there's a strong argument that that biases can be features too. It's all a question of whether they're being used in the sorts of situations for which they were designed, or whether they're in an unusual situation where they break down. In the case of vision, that's specially designed optical illusions, but practically all modern thought is outside the original design specs for our cognitive heuristics.