In most of the polls that I have seen, people are supporting an indefinite blackout. There is definitely some backlash, but overall it seems like people support the protest.
https://www.reddit.com/r/nottheonion/comments/148w58w/vote_s...
https://reddit.com/r/tennis/comments/148suem/rtennis_blackou...
https://reddit.com/r/SipsTea/comments/148sk76/further_protes...
https://strawpoll.com/polls/e7ZJGVOXBy3 (/r/stardewvalley)
A decent number of them show that people support an indefinite blackout, though there are some exceptions (like /r/tennis), where there is more support for opening back up. It's not universal, but generally people seem to be in favor of keeping the pressure on Reddit this way.
It's selection bias. The average user didn't care or know about the initial blackout. Now that they're affected, they're more likely to vote in these polls.