Irequest that when a new install is underway, a pop-up message gives notice, giving us the choice to delete the older version while installing the new version, or keeping the older version and still install the new version.
While it is true that a dialog comes up to update, the "advanced options" is collapsed and the "Remove Old Versions" is checked on by default. Either having the Advanced options expanded by default or having a secondary popup saying "Are you sure you want to remove your old version of Photoshop?" is necessary.
Max Johnson, Champion