There are many possible scenarios, but you have to consider how likely each one is, and what the timing of each will be.
Will society fail? Will wall street fail? Will you still have a job and source of income? When will any of these things happen, if at all? In what combination? Will we take back the government and institute more socialist policies? What is the likelihood that any of these things happen?
I can tell you one thing. While we have evil people in power, their power exists only in money. No matter how stupid or evil they will be, or how much harm they will cause, there are two things they fear most.
The thing they fear second most is a world where money is meaningless. The thing they fear most is a world where money still matters, but they are poor while others are wealthy.
Those evil people do everything they can to make stocks go up. They lay people off, we complain, but it makes stocks go up. They do evil dark patterns in their web apps and put all kinds of fees on shit, but it increases revenues and stocks go up. They deregulate and operate their businesses with no regards for safety or the environment. Super longs freight trains derail, forests burn, waters are full of PFAS, but all of that cuts costs and makes stocks go up.
The socialism that we want will make stocks go down. But that’s ok for us. We won’t need so much retirement savings if health care is covered by the government for free. We won’t need so much retirement savings if housing is a human right. Cut my 401k in half, but give me those things, and I probably still come out ahead.
Wealthy people on the other hand, stand to lose everything in that scenario. If stocks go down, they lose their power. Free government services are much worse than what they can trivially afford for themselves today.
Therefore, I personally believe that it is a good idea to invest in stocks as much as one is able. If the rich people take off and we can’t stop them, at least we claw back a bit for ourselves. If the economy fails for one reason or another, we will still be ok.
The only really dangerous scenario is if you are close to retirement and then the stock market crashes at the last second before you have a chance to recover. This is why the conventional advice is when you get close to retiring to move your money to a place with lower risk, such as a money market account.