I know I’m not the only one that has heard this. I get comic book and Sci-fi/fantasy writers probably lean left for the most part but I seem to remember liberals of the past being big on free speech and against censorship. Also I’ve heard SJWs complain about the original Star Trek because they had moved beyond race and you know everything today has to talk about race.
Stan Lee and Kirby are white males so they wouldn’t last today and on and on.
So what is a good response to this?
They're not really wrong. Trek in particular leans into communist utopia. Liberalism as an ideology has been used as a trojan horse for unrealistic human perfection. So yeah, there's a lot of progressivism in there.
Lee fucked Ditko and Kirby. It's all very typical.
As to a response, history is too nuanced to be able to lay it out plainly without getting a "wtf" look. You just have to ease real history in, bit by bit, and try to prevent rejection.