In this case does lib just mean “not communism”?

Liberalism is the ideology of capitalism. Thus "liberal" is everyone who support capitalism, that is basically starting at socialdemocracy and everything right of them - which in western countries mean literally entire political mainstream.

They only have two political parties, and it can be hard to tell the difference between them a lot of the time. They're both still going to push for more military spending, treat social programs with extreme suspicion, and probably go out and attack another country. The Wikipedia definition of neoliberal is this:

Neoliberalism is contemporarily used to refer to market-oriented reform policies such as "eliminating price controls, deregulating capital markets, lowering trade barriers" and reducing, especially through privatization and austerity, state influence in the economy.

Which describes both parties pretty well. Americans have a bit of a twisted view of liberal Vs conservative. Both their parties are pretty right wing in comparison to most of the rest of the world, so they often come down to performative acts. For instance, I'm trans. Neither party really cares about me, but the republican base hates me. So they each put on a big show of doing something about me. But they are both primarily interested in the same overall goals in governance, which is in line with neoliberal ideology.

So we just call them all liberals (although I think the republican party is becoming fascist, which is arguably not the same thing). Regardless, an average liberal's ideology is more compatible with fascism than with us.

To Republicans, "liberal" means communist/vegan/trans/Black/Millenial/baby killers/etc.

To Self-described Liberals, "liberal" means Non-authoritarian socialist/centrist/real patriots/pro-science/pragmatic/etc.

Basically, don't go on US social media to see political terms being used with any significant amount of accuracy. Most Americans are so politically ignorant that, even to many of those that describe themselves as politically-minded, these labels have essentially lost all concrete meaning.