Like you alluded to, the terminally online people who post the most tend to be those with neuroticism, isolation, severe anxiety, etc. There's a famous Reddit post about this I can't seem to find - "Everyone Online Is Insane" or something.
I really think this is why the past decade+ of American culture, politics, and society has been so off-the-wall insane. The Overton Window - another overused Redditism - of society has shifted towards the opinions of the neurotic and anxious. Those are the people whose words fill the comment sections and posts that we all read, which then infuse our minds to expect these thoughts as the baseline/median opinion of society.