I want to Disable App library, It's made my iPhone experience worse.

1. Threats don't work here. You can do whatever you want, and buy whichever device you want that fits your needs. FWIW, Androids have the same general feature of the App Library outside of the home screens.
2. Simply don't scroll past your last page of apps and you can totally ignore the App Library.
3. The App Library groups the apps by category. There is no point in customizing the App Library because its not intended for you to use it as your home screen, and its just an extra way of accessing apps if you cannot find them on your home screens directly. In most cases there should be very little reason for you to go there. And since you actually need to perform an action to get there, the best option is to simply not do it when you are on your last home screen. and if you do get there, just swipe bakc to exit it. There's no reason this feature should cause so much discomfort.
4. The App Library, shows groups of apps, you don't have to use the same 4 apps, it will show in each group the 3 most recent apps you have used from the group, and a group of small icons for your other apps in the category you can tap on to expand the group, and see and use the rest of the Apps in that group.
5. There is also a search feature above that lists apps alphabetically, and lets you search for a specific app if you need to.

click here ➜ Organize the Home Screen and App Library on your iPhone - Apple Support