If you think something is wrong in the society, fixing it is your responsibility. You can of course ignore it if you think the issue is not particularly significant or if it looks like other people are already handling it. But if the issue is important and contested, you are expected to get involved.
The deeper issue behind polarization is that people don't agree on the principles the society is built on. The Constitution may codify some principles, but too many people consider them insufficient or illegitimate. There is no fix to this apart from the vast majority of people agreeing on some set of principles.
I think everyone should try living a few years as a non-citizen in a foreign country. It gives a different perspective on politics. You live somewhere in the long term and see the issues around you, but you don't have the same rights as most other people and your responsibilities are limited.