Maybe... but something doesn't sit right with that assertion.

Anyone against concentration camps now gets the "liberal" slur thrown at them. Why is that?

As someone who grew up with a dad who listened to conservative talk radio, "liberal" has been used as an epithet for at least thirty years. I was genuinely stunned in high school when I met people who would willingly refer to themselves as liberals.

You'll have to pardon me for rolling my eyes at the notion that modern liberals have somehow made the term a bad word given the general path of conservatism over the last several decades, not to mention the last eight years specifically.