Another larger point to consider is that what we perceive as "just politics" is a (big) business to the participants: politicians, parties, pressure groups, media organizations, journalists. These folks exploit basic human traits (outrage, fear, tribalism ...) for monetary gain. Put another way : the trolls aren't trolling because they're deranged (sometimes, ok..) but because that's their business.

Long watch but quite relevant and interesting: https://www.youtube.com/watch?v=rg4IqrIpuQU&t=2440s