On the whole I agree with your point.
I was keeping a lot of media that Id never watch again because it was crap. Then I realised why keep it? I have no duty to provide it to others and don't need to repeat view.
Secondly, I found that my photo collection has thousands (literally of duplicates). Using python heading out was very easy to clean this out. I suffered some paranoia before automatically deleting the files but came to the conclusion that deleting by hand was not an option.
Finally, I think I've got a collection larger than I need (ie a hoard). I don't see it as a problem but my growth rate has slowed as I prioritise other things rather than collecting. I agree with your sentiment that there's better things to do than meta data curating but who am I to judge :)