For example, there are groups of people out there who believe the government is trying to give you microchips in vaccines and that they cause autism.
They don't. They follow a political ideology that tells them to ignore facts. Studies have shown they're truthful and able to discern facts if incentivised (paid) for doing so correctly.
Instead of being able to engage in some rational conversations with more rational people they get pushed out if they question things.
I can't speak for your echo chambers, but in my own, those who are simply questioning things are reasoned against, and only when one acts in bad faith does one receive bad acting in return. I have no duty to educate those who have no desire to be educated.
Now not only do they get more hardened in their beliefs, but now they also HATE that group that kicked them out.
If they don't support human rights just because some people were mean to them, then they never supported them in the first place. Bad people can be bad in their own spaces.
I think when people are forced to absorb more opinions and a differing set of viewpoints they become a smarter, more intelligent thinker.
I agree with this broadly, but every community has their own overton windows and their own safe space. I'm not looking to combat right wing fascism every day when I'm just vibing in my space.
Nowadays I find I need to call myself a more “traditional liberal” as a lot of current liberal ideologies have shifted to become more far-left.
Liberalism is a conservative ideology that upholds capitalism. If you're on the left, i.e. against the structural hierarchies, which is what the term was used to describe back when it was coined before the French revolution, you're not liberal.
Overall I just think echo chambers often can just be called a “cult”
You can make this argument for literally any social grouping. A family can just be called a "cult", and all too often actually are. A religious order, a fraternity, a group of drinking buddies, a workplace. "Cults" aren't measured by the social structure, they're measured by their impact and the level of control they take over the members within.