He’s demonstrating the fact that people only ever care about realism when firearms are involved.
Economics? Demographics and population? Geography? Realistic weather patterns? Feudalism? Army sizes? You've never heard arguments about realism applied to these things? You've not been around that long.
No one rants about the fact that studded leather armor shouldn't exist? Or that chain mail should be just called mail? Or that what's called a 'longsword' in D&D is actually an arming sword? Perhaps I should dig out my house rules for you if you think things like that don't bother people.
Nobody cares about whether plate armor is actually only 1 AC more protective than half plate. Nobody cares about how protective armor is against an actual long bow, or the fact that while plate armor may have an effect at stopping an arrow from a longbow, chain mail had no effect whatsoever. So if we wanted to be REAL realistic, then longbows would ignore all armor that wasn’t a metal sheet of a certain thickness.
Believe me, there are people that care about these things. Ever played GURPS? Chain mail has multiple AC's depending on the type of weapon used against it. Heck, there are bits and pieces of this in the original 1e AD&D rules, where different weapons got bonuses or penalties against certain types of armor.
But someone mentions firearms and all of a sudden we’re like “Oh, black powder! Oh, the smell! Oh, the historical accuracy of weapons of the time! Oh, it’s so over powered! Oh, it’s no different from a bow in terms of damage! Oh, we have to make it realistic or we can’t have it in our game!”
This is just normal nerdiness.
It’s bupkiss. It’s faux outrage. Nobody really cares whether or not it’s realistic, they just don’t Ike your modern mixing with their fantasy, so they come up with ways to nerf it or make it complicated or otherwise make it not palatable for their players.
I don't buy it. I think quite obviously they do, or most of them do care about whether it's realistic. What I suspect is these kinds of arguments are just proxy arguments for the claim, "You shouldn't care whether it is realistic, because I don't care if it is realistic." Incidentally, I've seen arguments from realism go the other direction with firearms as well - that they should be more lethal - because the writer couldn't swallow the idea of a gun only doing say 1d10 damage, and arguments break out citing things like the infamous 1986 Miami-Dade shootout (among other things) as to whether or not it was realistic for a person to be struck multiple times by a bullet and still be fighting.
But beyond that, I don't really see why there needs to be a rule about everything being equally 'realistic', whatever that means applied to something that isn't real. Fantasy and science fiction always have conceits in them, which the audience is expected to accept, that a certain magical thing or a certain bit of technology works. That's the conceit of the genre or the story. So, dragons can fly - axiomatically - because it is fantasy. However, outside of the conceits it's typical to try to be reasonably 'realistic', or at least 'believable' so as to not demand too much suspension of disbelief and so stretch the audiences into incredulity. RPGs are no different. It's not unreasonable to expect the audience to accept flying dragons, but still expect that something shared between the fantasy world and the real world - like say firearms - behave in a familiar and plausible manner. Firearms are real; dragons are not real. Why should we apply any sort of identical standard of 'realism' to them in the first place?