The reasons presented a good and valid i think. However, removing the functionality before a replacement is ready is very gnomey decision that I consider harmful. The Desktop metaphor works since decades and many users rely on it in the every day work and organizing their work. I use it as a sort of ToDo list, for example to quickly paste some pictures from my camera before properly sorting them… similar to how I use my real desk.
I hope Ubuntu Bionic Beaver will have a replacement ready before removing the functionality.
Edit: Sorry, I missed this reply:
Very good decision!