The opaque and capricious nature of Google's ban hammer, and the special type of an ML-driven bureaucratic nightmare they inflict upon users, affects many people that did nothing wrong at all. Real people and their livelihoods are affected by Google's policies, and that problem exists even if we choose to assume, without evidence, that the OP was a spammer.
I'd like to be able to judge this case for myself, but if the developer isn't sharing any of his prior communication with Google or any of his apps, why do you think they deserve the benefit of doubt?
You'll find a bunch of screenshots of random cheap looking apps that find wallpapers, phrases to tell to girls, spanish radios search.
So they most definitely rely on ads on their apps and not on building good ones.