The "Ethnic and national feuds" section seems like it gets a certain point across: things that seem silly in current context were extraordinarily important cultural touch-points at one point, and could well become so again. E.g., the U2 Irish/UK thing. Easy to laugh at today, but equally easy to understand why to some people at some point in time nationality difference between Irish and UK really mattered. Most flamewars are just real arguments that happen in the wrong time/place/tenor.

OFC some examples are clearly just the product of either drugs or a bad week, or more likely both.

Kind of like reading slashdot articles about "websites", hacker news articles about "capitalism", or newspaper article comment sections about "immigrants" in the late 20th/early 21st century. Or whatever. You get the point ;)