Vent/Rant:
Fill in the blank: strike, revolt, unionize, vote, etc
I was about to start this post off with something along the lines of “because we're all too fucking broke/tired!”, Which probably is true for at least some people, but as I started thinking about it, I realized that with that answer, even I am playing into what I think is the real answer.
Learned helplessness.
Whatever you want to attribute the source to: media, laws, society, rules, influence of the rich and powerful, corrupt politicians, fucked up broken systems, evil systems working exactly as designed/intended, brainwashed masses, etc (and in reality it's probably a combination of all the above), the result is a society as a whole which either brainlessly supports the status quo, or pisses and moans but doesn't actually do anything, because they feel powerless to enact actual change.
A few vocal individuals might shout about the need for change, and a lot of people might agree, but life has beaten them down far and hard enough that they don't take it any further than venting and ranting on the internet (trust me, the irony here is not lost on me). I scroll through this subreddit and see so many things that piss me off, but nothing ever seems to get better.
The thing about learned helplessness, is that for us to learn it, there have to be people teaching it, and naturally that will be the people who benefit from keeping us this way.