Screen rendering iOS = PDF, Android = HTML. Is this simplification correct?

Question

Android

This is the maximum simplification to the point of absurdity.
I know it's more difficult here and there.

In android, rendering follows the nodes of the DOM tree from the root . The layouts themselves are described by XML. HTML is a special case of xml.

But starting to study the development for the apple. At first I was surprised by the fact that a
PDF file can be used as an icon. And then I came across this fact

Most of the code written for OPENSTEP has gone into Cocoa and Mac OS X, but there are some differences. For example, NeXTSTEP and OPENSTEP used Display PostScript to display text and graphics on the screen, while Cocoa uses Apple's Quartz system (which uses the same imaging model as PDF).

Another fact is that PDF support was added to the android kernel only in version 5.1. The library even in the latest versions remains the same miserable. In fact, it is only available to get the page as an image. Opportunities for an apple in this regard is just a fairy tale.

Actually why such a simplification. HTML can be edited directly. It is practically impossible to climb into the pdf with handles.
If you look inside the xib file or story board, it seems quite readable at first glance. But editing in text form, as I did in most cases in android studio in xcode, does not work.

If we make an analogy for ourselves here we have a pdf, then SwiftUI is already becoming a normal approach, and not a terrible memory of layout on the PHP YII framework :)