Complete silence is impossible. At best only a tiny fraction of power users are the ones invested enough to care about the impact of what Reddit's doing, and are willing to do anything about it. The 99% of the platform who are lurkers, by and large don't contribute, and just want the platform back open and for everyone else to stop complaining are what's being fought over.

If you shut down enough of the platform - which the power users and mods can do by setting to private, restricting posting, or simply not posting when they otherwise would have - then the lurkers go to the site, see nothing to interact with and leave (or at the very least, spend less time on the platform as there is "less" to do). Over a long enough time span that would have started showing up in a big way. But it wasn't going to happen in two days. If anything, the blackout was so telegraphed and so much news got stirred up that it would make total sense if their traffic was actually not impacted or was even high for those two days (at least in terms of clicks and votes, not posts and comments). The lurkers are still valuable to Reddit though - that's where their advertising revenue is coming from.

People mass deleting their post history will hurt the platform. Some big subreddits staying private will hurt the platform. Some small subreddits staying private will hurt the platform. All of those things can bleed away users and diminish Reddit's usefulness and dominance. Really the ideal outcome is we scare them enough that they pull back to a more reasonable position and things can continue as normal. Maybe Huffman gets ousted and they plan a longer timescale and more reasonable pricing.