> but this is also the fatal conceit

I think considering the possibility that removing gradual iteration as a constraint, or considering the big picture, could lead to improvements of some natural designs, true or not, is unlikely to be fatal!

I don't see how anyone would just dismiss this point a priori. Both of those things seem, intuitively, to be fundamental constraints in evolution. Human biology plus technology leads to us out-competing every other similarly sized animal in any land niche we choose. The question is whether bacteria biology plus human ingenuity could have any similar advantages over biology alone. If you trust your snap judgment without extremely careful consideration, I just hope you're not in charge of the relevant policy decisions!