Of course it's up to the user to take action and abstain but if I open Reddit I see posts and can mostly scroll through my feed like it's any other day. If I wouldn't have known subreddits went private (and they didn't sticky a message) I might have not even noticed since I'll just see posts from subreddits who don't participate instead. The power that makes Reddit so good is working against the community effort right now.

The first thing I did this morning was open BaconReader from my homescreen before realizing what day it was. I replaced BaconReader with Jerboa to try and break the habit. It's not easy and I think Reddit knows it.