I don't know directly from any of this, because I am an unlettered redneck with air-cooled teeth and a net worth in the middle four figures. But if I had a serious prospect of ending up with genuine fuck-you money, and all I had to do to get it was keep doing what I was already doing and gut it out for a few more years, then that is precisely what I
would do, to the best of my ability.
I get that you're suffering, and I am not without compassion. But the kinds of jobs you're fantasizing about are kinds of jobs I've had. They are not without stress, as you imagine them to be. They are physically wearing and not at all secure, but most of all, the kind of stress that comes with those jobs - more to the point, that comes with those jobs being the best prospect you have - is not a kind of stress that ends, save to give way to something worse.
Your current travail, conversely, certainly will end, and based on what admittedly little I know about how startups work, you have a very real prospect of a great big payoff at the end of it. It would, I think, be the regret of a lifetime to squander that enrichment of all your years in search of a more comfortable day after tomorrow.