Applications like Google Docs would be impossible without each of the four things you listed being available. We had Google Docs that didn’t roll-your-own for each of the items in that list and it was called Writely and it was absolute dogshit (but super cool for its time) because those limitations were too extreme. And by extension it wouldn’t make sense to have Chromebooks as a category of hardware, because web software could never compete at a feature parity level with native software.