My previous job had more interesting work with half the pay. The company also had good enough brand name.
I feel if I stay in my current role, I will not be as sharp as I was. But I will easily be making 100k more per year which is a lot for me as a single bread earner.
Working at your overpaid gig only consumes 35-40 of those hours. Take the money and do whatever they hell you want with it on the side. If you want more interesting work... there is no more interesting work than the work you find for yourself.