With Rudin taking up so much space, and having such a distinct, easily-recognizable producing style, it can be easy to forget just how many productions with celebrities were NOT his. For example, I would say that Jeffrey Richards has successfully carved out a space for his own celebrity-driven play productions. And unless we hear otherwise, we have no reason to suspect that he's due for a "cancelling." David Binder is also in the mix there. Sonia Friedman is also pretty prominent, though her situation is slightly different, as she mostly brings things over from London.
Of course, we should be encouraging new producers to get their foot in the door, especially producers with a wider variety of backgrounds. But there can be room for them along with the established producers, many of whom are already providing high-quality (or at least interesting) Broadway plays, often with big names.
It's also worth mentioning that the non-profits have managed to score some pretty big names for recent Broadway productions. Maybe not as big as Denzel, Hugh, Bette, etc. But still some big Hollywood names. It still astounds me that Second Stage was able to score Captain America for their first Broadway production, and it barely got any attention. Not to mention some other stars who have done non-profit productions in recent years like Mark Ruffalo, Ewan McGregor, Jake Gyllenhaal, Anette Benning etc.