I couldn’t find the clip, but first thing that came to mind was the StarTalk Live with Buzz Aldrin and John Hodgman.
Hodgman: “maybe they’ll find H 2 2 2 2 O!”
Edit: crap, I have to call myself out. I failed to read completely, thought the screenshotted poster accidentally changed one part of the comparison, instead of deliberately changing both parts. If the original was molecules in a cubic inch of water vs stars in the observable universe, I read this post as atoms in a molecule vs stars in the observable universe.
Apologies, I discovered I was a fool and was excited to share my discovery.