Honestly, I’m not sure I would call “anime” a medium. It’s just a specifier referring to animation from Japan. The medium is animation, whether that be traditional 2D animation, digital 2D animation, 3D animation, etc.
A better comparison would be just that it’s like calling all American animation terrible.
And these guys aren’t even just calling “anime” terrible; they are calling pretty much all Japanese entertainment media terrible, with the general exception for live-action film and music.
Either way, they’re just trolling every time this comes up, so I’m not sure why you’re still going at this.