Because that's what a liberal is. Trump is more of a liberal than Biden or Hilary were. The left is not liberal at all anymore. The ONLY thing liberal about them at this point is that they strive for diversity and inclusion, but they have used authoritarian methods to get there, which is anti-liberal.

Russell Brand, Jordan Peterson, Bill Maher are all classic liberals that realized how anti-liberal the left has become. They are not conservatives (Peterson is just a bit in that he believes in some traditional Judeo-Christian values), they are liberals.

Liberalism means free speech, capitalism, freedom OF religion (not freedom from religion), tolerance of alternative thoughts and ideas, individual rights, free enterprise, and the right to private property. Which of these strikes you as what the left currently fights for?