As I have not read a good answer from Samsung I'm going to speculate a change in management with the usual change to something new that may be easier to market or a key programmer left the company and they can't find the team motivated enough to fix what was wrong or add what the (new?) management wanted.
This story has repeated many times in many companies so if I were to bet, that's my bet.
I use allshare all the time for my daughter to watch shows from our laptop that shes not allowed to touch but now the app disappeared and i have to use samsung link instead. The problem is, i have to install samsung software on my pc and i dont want to. It always worked before, but it seems as if samsung are insisting on the software being installed for sharing to work.
Is there an android equivalent app that im not aware of? I really dont want to install software on my pc when its dlna ready and should just work. I have used vlc in the past but same deal. Thats why allshare was so useful as it worked with windows easily.