To add another point of anecdote, I've also left a bad dev job for less money but better mental health overall. Such a good decision, but a difficult one to make.
Higher amounts of money yield diminishing returns. It's difficult to balance it with the added benefits of a low stress job (or one with a better commute, friendlier colleagues, etc), but putting the effort it's totally worth it. This includes being honest with yourself about what makes you happy in a job, which is actually much more difficult than it sounds (as it always it when you need to be honest with yourself).
I’ve never left a job and regretted. My criteria for a job are technology, environment and money. Once the technology got out of step with the market, it’s dangerous to stay at a job. Once you’ve been at a job long enough, why not leave for a better environment? As far as money, all other things being equal. Why not leave for money?
Higher amounts of money yield diminishing returns. It's difficult to balance it with the added benefits of a low stress job (or one with a better commute, friendlier colleagues, etc), but putting the effort it's totally worth it. This includes being honest with yourself about what makes you happy in a job, which is actually much more difficult than it sounds (as it always it when you need to be honest with yourself).