Thanks for the very thorough instructions, @reC!
As it so happens, I saw your reply just after returning from another marathon session at the wifi cafe in town. 
Oh well, I’ll for sure try out your suggestion the next time I’m there. Funnily enough, after this latest update’n’upgrade, I now also have two VLCs listed when I do a search in Software. 
They’re multiplying! And I’m trying my best to keep my system as organized and clutter-free as possible from the beginning, argh.
But seriously, just to make sure I understand things… apt autoremove is a housekeeping command that not only clears out files that are no longer required by a currently installed program, but also weeds out any clinging lingering files after a program has been uninstalled, correct?
Thus far, I’ve only run apt autoremove (i.e. with no program name such as gimp after it). So, I’m not quite clear on what this command does when it is followed by a program name (such as gimp). Does it only extract the unnecessary detritus related to gimp, but doesn’t uninstall the actual program?