Levelling Gaza or parts thereof is not a war crime —
Israel would consider it to be so, and others would consider it to be so. All you have to do is listen to Prime Minister Benjamin Netanyahu and you’ll see he argues VERY STRONGLY about how “MORAL” the IDF is, as an army, and rightfully so. Netanyahu uses EXAMPLES of what Israel does to avoid collateral damage to Palestinian civilians and so does the IDF too - to COUNTERACTS THE LIES that Israel indiscriminately allows Palestinian civilians to be killed.
Anyone who PROMOTES the exact same thing that Hamas says that Israel is doing, is helping Hamas in their propaganda lies against Israel.