Perhaps a compromise would be to prevent new installs of Joomla! 2.5.
In my opinion, a fire should have been lit under all Joomla! 2.5 users a long time ago to force them to update. December 2014 was 2 years ago and people are still using end-of-life software?
Perhaps calling it "end-of-life" is not catchy enough or too wordy. Perhaps a different term needs to be made to identify software that is no longer under active development and should not be used.
If end-users can't manage their Joomla! 2.5 site in the Softaculous dashboard, then perhaps that lights a fire under them to realize "hey! maybe I should update my Joomla! site to a version that is under active development"