Wiping out Hamas was always a pipe dream. I also don't think Netanyahu is stupid enough to think it was actually possible. I believe that was just said to hide the real plan: the liquidation of Concentration Camp Gaza so it can be resettled.
Even if they wanted to destroy Hamas, humiliating and murdering civilians while also leveling their homes and infrastructure is like, the worst way to do it. Because it further radicalises the populace and shows other organisations like Hezbollah they were right to denounce Israel outright.
What I'm saying is it helps them recruit desperate people.