Sorry, but that’s just not true. California’s coastal areas are hugely impacted by moisture blowing in from the Pacific. San Francisco’s historical average humidity in August is above 60% and the temperature rarely goes about 80.
If it’s rainfall you want, just go a bit further north. Coastal Northern California receives about as much annual precipitation as Seattle. You can find basically any climate you could want in the state – trying to make a blanket statement is pointless.
I agree with fast scrolling as the cause. All our social media these days emphasize endless new content to the point where it seems almost nobody reads the actual article anymore. I’ve seen posts on some of the politics subs on Lemmy where it’s obvious not a single commenter actually read beyond the headline because they’re totally missing some major point.
As to why they feel the need? I don’t think it goes beyond validation. People know the sort of one-line comment that will get them a handful of upvotes and agreeing replies, so they rush to be the one to make the joke first. It really becomes a drag after a while when what you’re looking for is actual discussion of the article. I find myself spending more time on Tildes than Lemmy because those sorts of low-effort replies are discouraged there.