It's funny that PG's "Blub Paradox"[1] is very close to your post, but
harsher and
stronger, but rarely draws much push-back when it comes up here, while your post is drawing flames like crazy.
I think PG's post is kinda shitty and is exactly the kind of thing you'd expect to see from someone who's very sure they've got things figured out, but aren't quite as far along their journey as they think they are, while yours is a simple correlational observation that probably has some truth to it (if there's an intellectually-challenging thing that's low-reward, probably the people involved will tend to be pretty smart, since they're just doing it as a hobby or for fun). Yet here we are, in the middle of a fire storm.
I think he's also dispensed exactly the advice you (basically) are, which is that you should choose some nerdy niche language if you want it to be easy to hire smart people cheaply, though I can't find it in a skim of that post and may be imagining it.
[1] http://www.paulgraham.com/avg.html