Why opine on massive communities?

A long-time participant in AI safety, Rationalist, and Effective Altruist communities reflects on the tendency to opine about these massive communities as a whole, despite only knowing small corners of them. The author draws a parallel to how people often hate Berkeley as a whole rather than specific parts, questioning why general opinions prevail over nuanced perspectives.

Today I’m at LessOnline, and yesterday I was at the annual CHAI workshop. Both are chock full of people I don’t know, with a good smattering of people I do. This is also my experience at other events like EA Global. I’ve been in the AI safety and Rationalist and Effective Altruist spheres since about 2008 or the beginning of EA , so generally go around feeling well acquainted with them and justified in opining on them. I gather that many other people do too. But reckoning with how huge they are now reminds me that of course I only know much about little corners of each, and each has many corners that are fairly different. Nonetheless, I’m tempted to opine about them in general, and much more often hear people opining about each of these communities in general. This reminds me of how people seem to much more often hate Berkeley than hate a particular part of Berkeley, even though the particular parts are fairly different. Why?