One key thought experiment I like to do is to project out a behavior pattern for all people and then asking whether that would be a positive or negative for yourself and society. If everyone were to campaign and push for the ideas they care about, I do believe that would result in a more informed and better society. Through the marketplace of ideas, we can fight through the differences and hopefully create better policy and have better leaders execute on our future.
I think for a lot of people, taking action to affect change for the community/society you live in is very natural. On a small scale that can be something like running for class president or joining your HOA. At a larger scale, politics is where change happens.
If you believe in a set of principles, it is sometimes worth your personal time, effort, and money to affect change. Hopefully you can see that from their perspective they are about their own future and this is the most effective way to impact that prospective future.
I also think politics (I'm not sure if it has always been that way, but I don't remember it like this when I was younger) has a lot of parallels to religion and that similarity is growing. I do actually believe this is rooted in the growing partisanship. That political answers are not "best solution vs a different solution" but "good vs evil". Partisanism relies on good vs evil. There's a John Cleese skit about extremism that always makes me laugh[0].
That's bound to stir up some passion on both sides, being that the stakes are rather high.
For me it’s because I see massive potential in UBI to transform society.
So it’s easy to understand there are others who are uniquely attracted to his campaign and want to do whatever they can to help.
He became a "bitcoin zealot" when that was popular, he became a AI fearmongerer, now he's a Trumpian provocateur. There is no cohesion between any of these identities other than the fact that they are reflections of what's popular at any one point. To me it's facade he's constantly draping over himself but to him that is identity.
I think humans are evolutionarily tribal and naturally some members are going to be more dogmatic than others. Myself not exhibiting that behavior, it's somewhat odd to observe from the outside.