Never cared for the protomatter plot development nonsense. Saavik's little spiel at David is amusing to me. David isn't responsible for what terrorists and rogue Klingons get up to.
He was trying to do something wonderful, and he was fully aware of what it could be potentially turned into. He was somewhat naive, sure, but the idea that he somehow needed to "pay" for taking a supposed shortcut does not track. By that logic I guess the first humans to use fire should have paid the price for the mass misuse of it later.
As David himself pointed out, Genesis may never have worked at all if he hadn't used protomatter, and frankly, we don't actually know that Genesis would have been unstable if it had been deployed properly. It also likely would not have become the "galactic controversy" had it been deployed secretly and quietly as was intended.
I was glad when Sarek stepped in to defend Kirk and co, along with Genesis itself.