It’s not exploitive if you like working on it. I can see an additional upside here (for tinygrad) that they better screen out people who are just trying to optimize for job prospects or money, who would do better elsewhere, and get people who actually like contributing.

Few people with no innate interest in the project are likely to ramp up and start contributing just for a shot at a job. Whereas if you’re Facebook or whoever you are much more likely to get people who don’t care about the product and just have decided they can make a lot of money by jumping through the right hoops.