The timeline has been

Last 5-6 years: COVID surge in HN brings in more people

Last 3-4 years: General rise in AI topics which have broad appeal and brought in a lot of people

Last 2-3 years: More overtly political discourse on HN bringing in more people

Last 1-2 years: Bots start coming in, some are very obvious, but they have gotten better and better to the point its hard to tell anymore.

Last year: Sharp rise in shallow redditor-style comments, especially in cultural/political discussions comments that are snarky but contribute little to discussion outside of affirmations like "Laws are for poor people"