Apple store already has a human review every update.

Apple can easily use some of their 30% cut of the scam app profits for validation: Apple certainly makes enough from “successful” scammy paid applications to cover costs as in the article example where Apple is also raking in $10’s of thousands from these fraudulent apps. Obviously free apps need a different mechanism.

Scammers rely on iteration to discover and optimize scam approaches, and to adjust when the platform changes things (e.g., to prevent the scam).

Scammers need an order of magnitude or more iteration over a legit dev to be very effective, so a per release fee will hit them much harder than legit devs.