When you are going to some arcade place in RL, you can find there good number of the machines that are giving you a random prize and it's perfectly legal even at the regions where gambling is prohibited, so I don't see how gacha machines are violating gaming policy.
Now, if gachas are violating the gaming policy, why they could not remain at Skill Gaming Regions, as well as all gacha shopping evens that could move there instead of just die?