Having been both a founder and an early employee, I wholeheartedly agree with this. Early employees really do wind up working nearly as hard as founders and the payoff is extremely disproportionate. The most likely scenario by far is failure, so your equity will be worth nothing. Your next-best hope is a moderately-successful exit, where the investors get their money back, the founders get enough to have made the endeavor worth their time and the early employees walk away with a few thousand. Hardly a year-end bonus at a bigger company (which you can expect _not_ to get at a startup). The Facebooks and Twitters of the world, where many/most early employees become millionaires are few and far enough in between to be essentially lottery tickets.

However, if you are totally fresh and want to gain some experience, it can be worth your time. The market for developers right now is such that you may not need to take such a pay cut vs a bigger company. This is the real variable. What are you giving up. And while you may work about as hard as a founder, you aren't as likely to wind up ruining your credit and destroying relationships with family and friends due to the incredible stress.

So it may be worth it for the experience. Just don't get sold on being an early employee as a path to riches via your equity. That path is vanishingly rare.