On the flip side, Unity is massively successful, and basically every indie game developer who has found any success eventually ends up porting their game to it anyway, precisely because of the cross platform benefits.
The problem isn’t that middlewares are bad. They are great: Unity and Unreal, your browser, Java…
The problem is mobile apps don’t make money. Games and web services do. The OP is talking about low quality users. They’re broke! They’re not incentivized to fix their own problems either! It’s all just a blub for them. So middlewares improve for the audiences where they’re at least viable, and stagnate when they support something that no one should be bothering to do in the first place.
Game dev is a different beast and in most platforms the development/tools are the same or close enough, also when building a game you rely only in low level API (Vulkan, Metal, OpenGL, etc) from the main platform you are targeting. But when you are building an app then you use the hight level API, that means you don't need to deal with font rendering, etc. You could obviously build an app with Unity, but it will not feel native, also IIRC Unity is awful when you need to input text in your game (in iOS at least, not sure how's Android side), it appears a input element above your keyboard while when using the native UI the UX is different.
The problem isn’t that middlewares are bad. They are great: Unity and Unreal, your browser, Java…
The problem is mobile apps don’t make money. Games and web services do. The OP is talking about low quality users. They’re broke! They’re not incentivized to fix their own problems either! It’s all just a blub for them. So middlewares improve for the audiences where they’re at least viable, and stagnate when they support something that no one should be bothering to do in the first place.