Yeah, sure, but "Frankenstein's monster" is a bit too long, there's no shorter version, and it's usually clear by context whether one means the monster or the scientist. It still bugs me, but as I've established before I'm annoyed by my own pedantry.
If you want a "shorter version", why not call him Adam? That's what Mary Shelly called the monster sometimes.
Because absent context, most people associate "Adam" with the guy with the snake and the fruit of knowledge.
You shouldn't feel bad about your own pedantry; the only people who complain about others' pedantry are people whose egos can't ever just accept the fact that they're wrong, they have to feel better about themselves by belittling the other person as if somehow they're the asshole for actually knowing stuff. If anyone, without any sense of irony or humour, accuses you of being pedantic make sure they fully understand just how much of a cunt they are before you walk away smugly, secure in the knowledge that you're in the right and that you're better than them simply by the virtue of actually giving a fuck about truth and facts. Accuracy matters. Try telling someone who mixes chemical explosives for a living, or a nurse giving our medications, that accuracy doesn't matter. Ok, calling Frankenstein's monster Frankenstein might not result in death but it's the principle that counts lol.
That's the thing, though. I'm not bothered by someone being precise when it comes to mixing chemicals or discussing technical subjects or whatever, because precision matters there. The Frankenstein thing, like the Oedipus thing, is
pointless pedantry. It doesn't really matter what you call the monster if it gets the idea across. I don't like my internal impulse to get annoyed at such things because it wastes mental energy I could be using to care about things that matter. Or, y'know, just not being annoyed at things that won't change anyway. Also because I suspect it's less about precision than it is about trying to show off how smart I am, which is another bad habit I have.