I feel like this didn't quite land as strongly as it could've, but I can't really put my finger on what would've worked better. Also we actually *couldn't* talk about aliens so quickly. That's what the collars are for. NICE TRY, SECRET ALIEN POLICE!
The angry comments I'm seeing aren't really addressing the point of the comic. (For the slow-witted: the point isn't advocating to make the evil mr bad bad guns super illegal forever and to kill the baby Jesus - it's to merely address, with simple conversation, our obsolete gun culture and starkly unique gun violence history. But good job emulating the comic unironically.)
They're also totally ignoring your delivery and style. I'm especially surprised to see another artist sulk-review a submission so poorly just because of politics when they've railed against people for this exact thing. You didn't even have to commit the cardinal sin of making fan art to piss them off. (Though you did commit the OTHER cardinal sin of being more popular than they are. Shame on you!)