Comment 7 for bug 1576859

Neither of those bugs are critical or affecting many people at all. So that's why no developers seem to have fixed them for 16.04 yet.

We have several orders of magnitude more bugs than we can possibly hope to fix. But I do understand your frustration -- I made exactly the same complaint to Canonical years before joining Canonical.

As for Gnome Shell bugs, those are especially unlikely to ever get touched because Ubuntu only really started supporting Gnome Shell properly in 17.10 (which is already past end of life). So Gnome Shell bugs will generally be fixed in Ubuntu 18.04 and later. I know Ubuntu-GNOME existed long before that, but it's not a flavor that the main desktop team supports.