Leftists aren't pro-government. Here's what happened:

The neo-liberal political establishment used to encompass the entirety of the Democrat and Republican parties. There were minor differences between the Dems and the GOP but they largely did the same things: bombed the same people, have breaks to the same class of mega-donors, etc.

In the early 2010s grassroots movements on both sides of the aisle arose primarily as a reaction to the economic crisis in 2008. On the left you had the "occupy" movement and on the right you had the "Tea Party". Both lead semi-successful but ultimately short-lived political instructions in their respective parties.

The Democratic party, being the more tightly-controlled of the two parties, really did a thorough job of wrestling back control from the leftists behind "occupy". The GOP did not and, after losing in 2012, the frustration bubbled-over and Trump was elected as a protest against the political system.

Literally every apparatus the political establishment controls has been working overtime since 2016 to beat-back Trump and the populist movement that put him in power. Leftists also hate Trump partially because they're subject to the same legacy media propaganda everyone else is and partially because he's actually against their interests. Given that the US is a 2-party system leftists ironically support the Dems and, by extension, the old neo-liberal political establishment.