But the blogger's position is one that is often met with hostility round these parts, for reasons that are unclear to me.

I think some of it is a defensive reaction to perceived possible vaguely-defined moral demands/condemnation. Here's a long comment I wrote about that in a different context.

Also simple contrarianism, though that's not much of an explanation absent a theory of why this is the thing people are contrarian against.

the parts of social engineering that I think LW is worst at.

What are those?