Overall, we have way more security than the ancient world did. Droughts are still a problem as the western US has been seeing, but at least we're at a point today where it just means food prices go up rather than food vanishing entirely and requiring migration to other countries or something.
As for stress, largely European workers don't seem to feel the pressures that American workers do, which probably boils down to in part a mix of higher taxes leading to better safety nets as well as generally much more vacation time from work. Also politics in European countries generally isn't as polarized, though by no means is it perfect.
I don't mean to say this was all perfect, but instead that when we talk about the stress of modern jobs, we should go beyond saying no one likes deadlines or bosses, because the real problem is the, for some people literally daily, uncertainty.
I think the key difference in the modern world is that success is not guaranteed, for reasons that may be well out of your control, and failure is scary with unknown consequences. We can imagine a world with pretty much the same jobs and the same work, but with more security removing the intense stress people feel.