The Political Propaganda machine in the US is now at full steam given how near their Presidential Election is, so we get innundated with "vote X" and "X is great" posts along with "Y is bad" ones.
Advertising has become so abusive that you can't browse anymore without and AdBlocker, and Political Propaganda is just a more manipulative form of advertising, often pushed by people deeply emotional bound to "their club" (funnilly enough, I also avoid Sports stuff, as it suffers from exactly the same problem) hence far more insiduous and aggressive.
Then to make it even worse, this electoral cycle in the US is all about doom-mongering with not a single message of hope or a bright vision for the Future: in other words, everybody is selling Fear, which at least in traditional Advertising is uncommon.