And Google doesn't really have a real incentive to fix the situation either. It's not really a "we need to fix this by next year or people will stop buying Android phones!" type of situation. They still make money on ads on Android, whether they are secure or not.

At least if you could adblock mobile ads to stop malvertising, as some already do on the desktop, Google may have had a bigger incentive to fix it. But they removed that incentive a long time ago when they decided adblockers aren't allowed in the store.