Well the lower the job pays, the more likely you're stuck in it.

High-paying jobs pay enough to walk out anytime you feel like it.

That removes a ton of potential stress right there.

It is true that those jobs tend to get more stressful. It was meant in a context of engineering salaries, where the lower ones still provide a fairly luxurious way of living. What many industries do to low wage workers is nothing else than abhorrent and the tech industry supports this with surveillance technology. The security department is especially guilty here.

Being able to leave a job at any time (due to savings) is a huge comfort.

This is anecdote, but the higher salary companies I've worked at have been much more competent, productive and happier in general.

Most of the stress I've encountered in software development has been due to complexity brought by inexperience. They were all lower paying companies.