I don't think it's a serious statement, they're just taking it to a ridiculous extreme to demonstrate the point. Or maybe I completely misunderstood, who knows!
The problem is that “slippery slope” arguments don’t demonstrate anything.
Remember when the USA south kept saying “what’s next, marrying animals?!” With regard to legalizing equal marriage?
This shit doesn’t mean anything because rational people are capable of understanding nuance. So they’re literally just here to say stupid things and waste peoples time because we’re obligated to respond to this stupidity to make sure that nobody confuses lack of response with validity.