No, it wasn't just about wanting her in all quadrants. It was about all quadrants AND having exclusivity. You're picking and choosing. "FCG: SEE IF YOU CAN HAVE YOUR GRUB, AND CULL IT TOO?? FCG: THAT WAY YOU HAVE HER ALL TO YOURSELF! CCG: FUCK YOU. FCG: YOU WANT HER IN EVERY QUADRANT LIKE A DESPERATE FOOL." Yes, the way Karkat went about it with Terezi WAS unhealthy. But wanting to be monogamous in itself if done right, like the Signless did, isn't inherently unhealthy.
I mean, honestly it could be? Yeah, and of course it’s not inherently unhealthy at all, but also it could not be- This is a Future Karkat vs Past Karkat conversation, they throw jabs at each other, bring out the worse of each other. Exclusivity could mean Monogamy as much as it could mean Obsession, and growing beyond Obsession MAY as well be growing beyond Monogamy, which is not necessary, but not unrealistic either. I’m not saying there’s definitive proof about Karkat, Dave and Jade being together, but like. You could absolutely read it that way and there’s nothing wrong about it. Same way you can read Karkat’s crush on Terezi as proof of his monogamy and have him be with Dave and just be chill friends with Jade.