If you were to go into a bar today and shout out "Join the army! All bugs must die!" or something, do you think everyone would know exactly what you were talking about? Or would they maybe think you were promoting some fascist, hateful action among the many others taking place currently?

First, this isn't a bar. This is Lemmy, a community on the internet mostly filled with nerds. This is one of the most popular games at the moment. Also, even if they didn't know the game, odds are they know Starship troopers, and this is just an expanded meme of that.

Second, no I don't think anyone hearing you say to kill all the bugs will think you're a fascist. They might think you're crazy, but, as far as I'm aware, there aren't giant bugs we're at war with in real life.

I think there's almost zero chance of this being mistaken as a sincere fascist post, and it's pretty much harmless.