These are more like byproduct of the fact that web apps are built on the stack not suited for modern UI apps. It's literally a text typesetting engine pretending to be a rendering engine for high-performance UI.
So, it can also be framed as:
- everything is selectable, even what shouldn't be - buttons, drawers, video players, etc - content is zoomable, which most of the time just breaks UX in hilariuous ways. Developers have to do extra-work to either disable zoom or make hacks/workarounds.
"Everything is selectable" and "everything is zoomable" makes total sense if it's a blog post. If it's a UI for the modern app, it does not.
This is an outdated view of the web. Catch up or be left behind.