People keep using the term "star" too loosely and overlooking the fact that there's levels to it.
No one's been a draw like that in years. Cena was probably the last one. But that's not necessarily the issue, rather it's a symptom of a larger issue. The issue is that the product has nothing people want to see on it and don't seem to be invested in presenting something someone other than Vince McMahon would want to see (case in point: I live pretty damn close to Staples and you couldn't pay me to go to that RAW).
For people saying that the brand split is the problem, fixing that won't fix the booking issues because of the above. If they can't use the full roster of one show properly, why would they be able to do the same with two?
WWE has deep issues as a company. It's papered over by their other business deals, but those rights deals have a shelf life and MBS won't need them to launder his image forever (then again, I'm pretty sure Vince and Nick Khan know that more than anyone else, given their moves over the past year or so).