I don’t know about sanity, but it’s very logical when you remember that Hamas is a terrorist group that sometimes governs rather than the other way around.
The genocide is pretty much the best thing that could happen to them. They may pretend to care about Palestinian lives, but in reality they only care about their own power and influence.
And how does a terrorist group gain power and influence? By radicalizing people to join.
What’s more radicalizing than the myriad daily atrocities of a brutal apartheid regime supported by the most powerful countries in the world? Very little if anything.