Well it's like this:
The lefties believe that rights are granted to the individual by the collective. That those rights may be revoked at any time. They believe that individuals MUST be sacrificed for the greater good.
Their main policy is divide and conquer and this strategy has evolved as people wake up to it but it always comes back to the rich vs the poor.
They seek to use the tyranny of democracy as mob rule by agitating groups to vote against smaller groups with emotional statements whilst burying the facts.
They use welfare to bribe people to vote for them and run up massive unsustainable debt (The end goal is to make everyone dependent on them and under their control).
They believe fervently that they are intellectually and morally correct and that they are justified in using whatever tactic they can in order to win.
They have infested an infected the entire popular culture with their nihilistic, morally relative world view which gets rebounded by politicians and bureaucrats. Movies and stories are ruined by their constant political messaging.
They hate Christians, white people, men and capitalists and are ever searching for ways to destroy them.
A conservative or a libertarian will say "live and let live" - Leftists say "You MUST live this way"
Every leftist policy implies force to coerce people to do what THEY have deemed the correct course of action. They do not care for anyone's opinion but those of their own design. Think political correctness and the mantra of tolerance/intolerance.
At any opportunity if they fail in a debate they resort to slander, insults and violence.
Multiculturalism is a leftist government program
Immigration is a leftist government program
Leftist governments provide services to justify tax increases and only seek to grow and become more powerful - Think Border Force super ministry.
I can not live my life the way I want to because the left wants to control what I think, say and do, all the while tearing down everything I care about.
No matter what the lefties say. Hitler was a lefty. The only difference between socialism and national socialism of the Third Reich was the divide and conquer message; one was based on class the other on national identity. How is it that on the political compass that socialism can be on both ends? Answer they can't.
The left is all about concentrated power to an ever shrinking group of elites. The right is all about the decentralization of power and responsibility back to the people and that the rights of the individual supersede that of the collective, such as; Presumption of innocence and the right to a fair trial, freedom of speech to speak truth to power. All the things the lefties want to take away.
That's why.