I use Android and iOS constantly (mobile dev), and iOS's multitasking on the iPhone X is as easy as Android's (swipe the bottom of the phone, same action as double tapping the app switcher icon on Android). Same with split screen, I use the all the time on iPad.

What’s alt+tab without a physical keyboard?

An easily-understandable reference for non-Android users. One of Android's buttons (the square) goes to the app switcher, it functions as alt+tab on its own.

we have that on iOS though, it's the swipe up and/or to the right gesture. It's honestly the fastest way to switch between apps on any device I've ever used. the android dedicated button feels clunky in comparison.

I understand it's a "hidden gesture" and thus all the UX complaints apply, but from pure observation most android users use the app switcher about as often as PC users use alt+tab... basically not as many as you think.

Most mobile phone users who are even slight technophobes will switch apps the old way from the home screen or app drawer. at least with the iPhone the "going home" behavior can accidentally surface the app switcher which after enough exposure might train such users to use it.

Idk, I kinda hate all the UX paradigms that android introduced, it often felt like they ignored much of what xerox parc taught as objectively good UX and tried to go it on their own, only to have to relearn all the same mistakes that Mac and Windows learned over the last 3 decades.