Anyone actually tried the carnivore diet long-term?

I've seen a ton of people online swearing by the carnivore diet meat. They claim it fixed their gut issues, gave them crazy energy, and cleared up their skin. That last part caught my attention because I've had pretty bad eczema for years that nothing seems to fully knock out. But then you hear doctors warning you'll get scurvy or destroy your heart in six months. I'm genuinely curious how real any of this is.