The world's best vegetable dish is average at best compared to a dish that includes meat.
That's an opinion based on my taste, and an opinion a lot of omnivores share, it isn't wrong... Neither is it right for you - however it does seem to be the opinion most hold.
True for steaks, chicken, etc, but not true for fish IMO.
That said, I think it's not true that one is inherently better than the other. Everyone has preferences of course but I think people have been sold this idea that it's not a real meal if meat isn't involved and damn you're missing out on so much good stuff if you have that mentality
I always thought that this was true but after being a vegetarian for 2 years whenever i eat meat (because there is no other choice or something) I find it doesn't taste "that good" anymore.