"At what point will people get frustrated and stop submitting reviews ?"
Probably never so long as the incentive is a free month of access to the reviews. It took too long under the old system for reviews to get published, which is why it went to the vote system. The things people object to really aren't that big of a deal. And they're obvious.
Just because "Amber" sucked customer Bozo's cock bareback doesn't mean he needs to tell the world about it. If some guys just can't help but overshare, then that's on them, but there's probably lots of other guys who would mind if "Amber" has to move on because it's now too public that the management is looking the other way on her. Maybe not all the managers are as permissive, and "Amber" only dances when "Don Pablo" is managing because she can suck n' fuck and he doesn't care so long as he gets his cut. Then Bozo just burned "Amber" and "Don Pablo", and maybe they both go. Maybe all the manager's are letting things go but the owner doesn't know. Lot's of shit goes sideways when info is too easy to come by. This site has PMs for a reason.
For me, I tend to think I'm fairly lax on what I approve for reviews. If it looks like someone put in a decent effort and the review looks legit, then it gets a pass from me. If a review has zero information, is obviously fake, or would get a dancer I'd like burned from a club I'd like, then no.