You couldn't make this movie today. That's because the alien would just walk around in a bathrobe, tentacles and ribs sticking out everywhere. When challenged, it would just say:
"Oh, I guess that anybody who has different opinion about which biomass ought to consume which is a "MONSTER" now? So much for the tolerant left!"
The movie was a total bomb back in the day. There's a review saying that it's even worse than Blade Runner (which came out on the same day and was also intensely disliked). It almost destroyed Carpenter's carrier. They hated it so much they nominated fucking Morricone for a Razzie (some unused tracks were later used by Tarantino in The Hateful Eight and won an Oscar...).
As soon as you accused it, it would announce that it was running for president, delay judgement for four years, win, and then spread the infection worldwide.