Paul Graham, way back in 2009:
More generally, you can have a fruitful discussion about a topic only if it doesn’t engage the identities of any of the participants. What makes politics and religion such minefields is that they engage so many people’s identities. But you could in principle have a useful conversation about them with some people. And there are other topics that might seem harmless, like the relative merits of Ford and Chevy pickup trucks, that you couldn’t safely talk about with others.
And the key takeaway:
Most people reading this will already be fairly tolerant. But there is a step beyond thinking of yourself as x but tolerating y: not even to consider yourself an x. The more labels you have for yourself, the dumber they make you.
Run a site like OSNews for almost a decade, and you’ll see this article come to life every single day.