I’ve never understood this obsession. Odds are you’ve never heard of Ceres, but it was once called a planet. It’s now considered a dwarf planet, like Pluto. Pluto is also less massive than Eris, so if you include Pluto you should also include Eris. None of these have cleared their orbit though.
I understand it’s frequently just a joke, but it’s always rubbed me weird because some people actually became science skeptics because “suddenly Pluto isn’t a planet” or whatever. Really the reason is because the list would get really long if we included everything.