Sure, it was a lot worse pre-ACA. Thankfully, it's quite easy to purchase individual insurance these days (I pay $160/m for mine). We'll see what happens with the Republicans.

More importantly, health insurances do not at all sufficiently explain the differences in salaries. Google will hire you here and give you great health insurance, even though they're also paying very well.

Also, the notion that it requires really high taxes to implement single payer is simply not true. Singapore, for example, has a robust public health system while also having some of the lowest taxes in the world. After all, companies are already paying for insurance here. If we socialized it, I wouldn't expect tech salaries to drop.