@lrhodes
Here's an example from as early as mid 2019, but I think there were similar attempts even before that, maybe not blank sheets, but obfuscated messages still understandable by most: https://www.currenttime.tv/a/protest-with-empty-paper/30063501.html
We were stupid enough not to translate our news into foreign languages to make more people learn what's going on here.
IMO blank sheet wasn't good for making a statement in that case, but it did expose the absurdity of police state really well.