I think fame can be a bit of a burden. If you have a kind of guru status you might be averse to taking risks that others think are foolish. Whereas when you were an unknown that wouldn't have mattered.
But, that's a minor factor. This is what I was thinking: celebrity is associated with at least one past success, and it becomes like a characteristic of the person, for at least some time. Business success has many more factors, some of them effectively random, and not associated with the person.
So we should expect reversion to mean for the entrepreneur's post-celebrity ventures. While they may succeed more often than others over time, their next big venture would be highly likely to be a flop.
But: Smietana's post linked to research which suggests that I'm actually totally wrong here, and entrepreneurial success is more of a function of skill. Maybe that suggests that the successful entrepreneurs are the ones who learned the best during their first venture, which makes replicating success easier.
I believe he means a negative correlation (not a negative personality); as in, the more famed celebristatus the less "success" which, was not supported in his original post.
Edit: OP edited with the Quora post, which links more successes (or celebristatus) leads to more success.
How so? Is your suspicion based on the possibility that fame changes people for the worse?