Sounds like Apple gave you a way to solve your problem. Personally, I like the animations, but I'm glad users have the option to turn them on and off as they wish.

The problem is that switch is global on iOS. I don't want to remove all animations, just some of them. Android has the same problem here: I want to disable many animations because I find them annoying and intrusive, but some critical animations like loading spinners break when animations are disabled, so I do the next best thing and increase the speed.

At least iOS lets you change the font size for each application independently, which is a feature that I make heavy use of. I like larger fonts, but sometimes this results in text being truncated too early, and being able to selectively reduce the font size makes it feasible to have a larger default font size. For whatever reason this is not possible on Android, and changing the font size takes several seconds to kick in, so even manually boosting the font size for certain cases via a shortcut or automation is annoying.

I think it makes sense to have the page turn process take a little time and have a little bit of visual transition. Our visual processing system isn't great at knowing whether a new screen of text has been loaded, especially, if we're blinking when it happens. Having a brief animation helps us know that yes, you did just tap the edge of the screen, and accordingly the page has been turned.

You can turn most of them off. That said most of us would prefer more skeuomorphic UIs