Don't worry lol I've had this exact debate as well, but was not sure how people here feel about it so I had to preface it.
Got any good arguments to make people understand? I've basically just given up trying as it has never yielded results
What Yousef said, they're on Steam, they're on consoles. Typically, VNs have gameplay elements in them, an example would be the Ace Attorney series. Sure, traditional VNs may not have any real gameplay besides just reading, but at the end of the day if it isn't on paper or some kind of digital book format it's a videogame.
Visual novel is a videogame genre, just like third person shooter, first person shooter, platformer and the list goes on. I mean, it's in the name itself "VISUAL" novel, meaning there is an element here at play where you need to visually see what's on the screen, a book can be read to you by someone else, VNs heavily rely on the medium for art, animations and again in some cases gameplay elements.
This doesn't diminish or devalue VNs as an art form or literature, if anything it makes them more unique and a different kind of experience to a regular book or comic book, it's just that in my experience a lot of VN fans think that having their favourite genre labelled as a videogame is some kind of bad thing for some stupid reason.