Amazon Underground was of course a very similar pay model. It was a resounding failure.
This type of pay model is a terrible one for developers. It may be fine if you’ve created the next Fortnite or have a huge name already; it’s terrible for everyone else - especially indie developers. I crunched the numbers on Amazon’s similar attempt back in the day, and the payoff was abysmal. I forget the exact details, but in general I would have had to increase my player base by several orders of magnitude (way beyond what is reasonable to expect for an indie game of the type I had) in order to match the revenue generated by ads and premium sales even on Amazon (and sales on Amazon were never good to begin with). I know of at least one developer who did take the jump, and got badly burnt.
It’s also bad for users, because it grants extreme financial incentive for devs to make their games as predatory as possible (that Apple - and Amazon before them - sell this as somehow an improvement over IAPs is just… ugh). There are so, so, so many ways to pad out gameplay time: add seconds to loading screens, saves, unskippable curscenes, stretch out each animation, lower walking speed just a bit. Everything adds up to money -> and everything will end up being deployed by developer desperate to make this work and competing with each others for a limited pool of money. And that’s before you’ve even gotten to all the horrifying psychological tricks that games can deploy to get people addicted. Think IAPs are bad? The tactics deployed here will be even more lucrative, because the game doesn’t even have to work to get you across the threshold of paying for stuff - they just need to get you to spend “free” time in the game.
It’s an “interesting” if slightly puzzling move from Apple, though. Amazon Underground pretty much destroyed the viability of Amazon’s app store since it tanked any incentive for people to actually ever pay for games on the service. The behemoth that is the IOS app store won’t die as fast, of course, but it will be interesting to see what effect it’s going to have on revenue there. I don’t expect it to be positive.