having lived through that period and relying on the internet to do my day job i didn’t notice.
also if you look at the history of the bill, there is no mention of public opinion at all. They shelved the bill due to lack of agreement.
Well, speak for yourself, not "most of us". On 01/18/2012 the HN front page was basically nothing but SOPA/PIPA content:
https://news.ycombinator.com/front?day=2012-01-18
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:
https://arstechnica.com/tech-policy/2012/01/pipa-support-col...
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.
I very much noticed. It was all over pretty much every major site. I'm surprised to hear of anyone online that day that didn't notice.