I disagree with this.

I think a natural intuition about a moral values domain suggests that things are likely to be non-linear and discontinuous.

I don't think its so much saying the claim is wrong in simple cases, but its still correct in cases no one understands.

It's more saying the alternative claims being proposed are a long ways from handling any real world example, and I'm disinclined to believe that a sufficiently complicated system will satisfy continuity and linearity.