Yes, this is key. There are many cases like this (and CSS pseudo-classes, and the drag and drop API, etc.) where the browser platform gives you convenient ways

Yes, this is key. There are many cases like this (and CSS pseudo-classes, and the drag and drop API, etc.) where the browser platform gives you convenient ways of avoiding the problem. And certainly, take advantage of those where possible. But they don't eliminate the problem in the general sense.