- A functioning public transportation system (I was living in a city of 100k people and could get around by bus decently. The worst bus lines still came once every 20 minutes).
- almost free access to culture
- Being able to get your passport done in a week, not six. Maybe not the nicest people, but things happen a bit faster
But I think the core reason you don't see super-high salaries is because the system makes offering absurdly high salaries very costly, instead preferring for more people to make reasonable salaries. You have things like the fortune tax so that even if you don't have a salary, if you have too much money you'll get an extra tax.
It's a feature of the system, not a bug. The glib explanation is France hates rich people. Not everyone likes it but at least everyone gets 6 weeks vacation. And if you don't have a job you can still have a place to live and not live under constant fear of eviction.
France hates lots of things but it sure loves red tape.
And for culture, apart from some museums when you're under 26, public libraries and cultural festival, you have to pay for the rest (theatre, concert, expositions...), even if they are subsidized.
I have the Market Secure plan. I'm not pretending it's terrific insurance, but it'll cover me if disaster strikes and avoids the penalty.
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.