DY: Ah, interesting. My point is that you need sources to dispute their source-less change to Judaism. Otherwise, what makes you more right than them? It’s just he-said-she-said. You might be right because you happen to be right, but that’s really not how Yiddishkeit works.
R’ Chaim was a Chiddush in how to learn the Rishonim, which is fine because, by definition, there can’t really be a Mesorah from Chazal on how to learn the Rishonim. He didn’t change how to learnt he Tannaim and Amoraim.