TBH, populism is bad when that populism is just a cover

"Populism" isn't a thing at all. It's an empty buzzword that doesn't mean anything but "thing that I, the smart and rational adult in the room, do not like and think is vulgar and cringe," and it gets applied to everything from things that are popular and appealing to the public to things that are intensely elitist and unpopular. For example, being against war is always populism, and thus bad, but being for war in too honest a fashion is also populism, and thus also bad. Civil rights are populism, and thus bad, but being against them is also populism, and thus bad. It's a framework that exists to defer all authority to a specific sort of tepid managerial technocracy where the government has to do bad and unpopular things because that's "pragmatic" but they have to be contrite about it instead of admitting they like being corrupt, bloodthirsty assholes because liking being the bad guy is bad populism stuff. And they're definitely not allowed to even try to be better, because trying to do good things and be popular is populism, and thus bad.

True that

But I do see libs who honestly believe that because an idea has popular support, that means it's populist and therefore bad

It's kind of weird