[Groxx]

tl;dr: inconsistent interface, no recommendations when nothing can handle it.

Generally quite true, though the 'share' icon on Android is pretty consistent. Easily 95%+ of the apps I've used have used that same icon.

A lot of this would be / could be solved by having some way you could replace the system's chooser. I hadn't thought of that before reading this article, but that would be pretty darn cool, and could be a significant improvement.

[Zigurd]

If you don't like the system picker, you can pick the target before the StartActivity call using your own UI.

[Groxx]

True, but this would be even more inconsistency, as each app has to do it themselves.