Ask HN: Why can't I open an ePub image/chart in a new tab?

Most of the time when I read an epub, it's on one of two devices. On my cheap android smart phone, or on the crouton chroot on my Chromebook. On the Chromebook/crouton, I use the Kindle Cloud Reader from Firefox. If the epub is unencumbered, I use Calibre.

As is widely appreciated, diagrams, tables, charts, etc, are often too small to be useful, are inconveniently split over two or more pages, but could easily be LARGER and FULLY CONTAINED on one page were the epub reader smart enough to open it (upon demand, of course) in a new tab/page within the epub reader itself. And why not ignore current margin settings when displaying figures and such in a separate tab -- to maximize chances of displaying the whole of the figure? Further, why shouldn't one be able to rotate such an figure or image in a tab with a click or a quick key-combo if the data would be easier to view that way?

And why the fixed size of images in epub readers? (This may be something that is not true in all readers.)

Does anyone know why this isn't done, or if it would be a particularly difficult task for creators of epub readers to effect?

Go easy on me if your epub reader does one or more of these things. My experience is limited, my ignorance is great.