Sorry what?! I was in Australia and even from here it was obvious it was happening. Maybe go back refresh your mind on old HN posts. Sorry not meaning to be rude but the digital protests of the day were very significant. Lots of media coverage and site blackouts and banners and average punters waking up to the interruption. Stacks was going on. You can even watch Internets Own Boy doco where it’s covered.
As for your claim they had no effect, that's not what the sources from the time say—on the day of the protests 13 senators announced their opposition, including 5 former co-sponsors:
When you lose five co-sponsors in one day and that day happens to coincide with the internet shutting down, I don't find it very credible to try to claim that there was internal dissent all along.
the protests had no bearing on the outcome of the bill. most of us didn’t even know they were taking place.