This is an annoyance to many people because a sticky note they didn't want all the sudden shows up on their desktop. I just had someone 2 days ago ask me how to get rid of that.
This Middle Click on Desktop feature could be awesome though, replace pasting with the quick application menu.
The quick launch menu provides an exploratory "oh that's cool" instead of "what is this, how do I remove this note thing" reaction.
Additionally, If this were done then I think the Application Menu should be adjusted to display the Application Names not the descriptions as described in https://phabricator.kde.org/T7977