Yeah, again, there are some incentives to fabricate evidence like career advancement. Now why should those, on a mass scale, outweigh disincentives like getting caught in an adversarial process and (presumably) some qualm about regularly convicting innocents and regularly letting guilty parties run free in communities. Easy to argue in particular cases but I haven't heard the basis for a trend.
What adversarial process? If the prosecutor loses the case, the defendant doesn't go to jail but still receives a very big punishment and the prosecutor loses nothing. And prosecutors never prosecute themselves for false prosecution.
This sounds like you’re imagining how prosecutors as a group sort of feel about things, generally, and that this notion you’ve thought of outweighs the demonstrable real-world system where prosecutors are awarded for convictions, full stop.