Your ability to participate in political organization and not immediately be killed or thrown in jail depends on the people who are in power. The United States isn't immune to regressing to that society, and it's very clear the Republicans are doing what they can to move in that direction.
Voting for the Democrats and doing nothing else is far from ideal and won't fix the institutional problems, but it will help prevent new major problems, like mass murder for criticizing the government, from popping up.
Voting for the Democrats so you can continue activism is step one, and is an important step. It's also a trivially easy step with no downside. It's just not the only step.
Too true. Listening to Sanders from the 80s is the same as listening to him today. It's shocking how little his views and rhetoric have changed while being absolutely correct from the beginning.