I don't agree with opinions representing the holder's truth, at least not all the time. For most people, some of their opinions are more like part of their identity. Identifying with that particular belief lets them belong to some group or tribe, or lets them see themselves in a certain way. They see these beliefs as axiomatic, rather than a fact-based opinion (not that most people would ever admit this). Attacking that belief, in their eyes, is tantamount to attacking them, because they see it as an attack on part of who they are. And to change that belief, part of them has to die. This can be useful to keep in mind when someone comes along who believes odd or even reprehensible things even in the face of bullet-proof logic and great emotional rhetoric.
This is so very true. Attaching things to identity is a tried-and-true methodology for propaganda and control that is, unfortunately, very effective with many people. It's this very reason that certain parties are so interested in linking political affiliation and lifestyle to people's internal sense of identity. It makes it so much easier to control discourse when everything is earmarked into what party you are affiliated with or what type of lifestyle you should be living. It's this reason that discussions about capitalism become left vs right, rather than discussions about economics, culture, and society. Why some people can't believe in or discuss issues like Climate Change without it becoming a conservative vs liberal issue that somehow affronts them personally, rather than a scientific and social one. And why corporations franchise out identities to people, rather than products, targeting impressionable youth, retired biker daddies, tattooed bearded whisky sipping malcontents, house moms, and hipsters based on what values they should have, beliefs they should hold, behaviors they should adopt, the type of people they should associate with -- and, of course, what products and services should go along with that lifestyle. Wink. Wink. Identities are big business these days. Data driven cash-cows. The present and the future of marketing, politics, and culture. And it is technology and science that are driving this beyond anything we could have predicted even a generation ago; which is probably one downside to having never been where we are as a society, today -- we don't yet understand the impacts and problems that come with this data driven, identity peddling world we have constructed around us. Nor do we have the regulation and the rules to properly regulate it the way it should be.