It comes down to how much you're spending. People are spending hundreds of dollars (some spend thousands) on Genshin and other gotcha games. If you're spending hundreds of dollars and you can get 30% more virtual currency for your money then you're much more likely to go out of your way to do it.
The IAP model became dominant on mobile largely because of Apple's store policies and their refusal to allow other forms of distribution. Meanwhile Steam and many other channels are largely pay-once, and they exist only because of the developer freedom that you decry.
No, the IAP model became dominant because the unwashed masses can’t be bothered to spend a few dollars or even just 99¢ for a copy of software that oftentimes took many months if not years to develop, to say nothing of on-going support and maintenance costs. Too many people (in general) are just flat out fucking cheap and too many devs/companies are willing to resort to stuffing every app with ads and tracking.
It's so hard to find anymore. Digital board games are one exception, there are a lot of really excellent ones with great replay value for a fixed price. Scythe, Root, Spirit Island, Railroad Ink, Wingspan, Through the Ages, Galaxy Trucker...
It's even worse when you have kids... your toddler gets upset because the very fun looking princess puzzle she's trying to play "is broken." In reality, it's just pay-walled.
