If the reason they can't find work is because employers are unwilling to offer relocation, why on earth would those employers be pursuing the even more costly and complicated relocation of foreign workers? In general, I genuinely think there is a domestic talent shortage. Of the talented developers I talk to about new opportunities, a majority are overseas—if we could bring them in easily, we'd readily do so (and pay them market rate). But the visa process is so tenuous and expensive at this point that it's incredibly challenging for startups to even consider that route.
Moreover, I'll put my money where my mouth is. You say you're a capable engineer. If you email morgante@cafe.com and convince me of that, I'd be happy to offer (a) relocation, (b) training in our stack, and (c) NYC market salary.