[gordaco]

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).