Careful with that advice. Reddit is full of people who initially didn't have big apetite and didn't eat enough, ultimately failing the diet.
I'd suggest to start with priming first and move to eat when hungry later.
There is no need to track calories or macros on the carnivore diet, especially when starting out. Eat when hungry enough for a meal. Stop when full. Don't eat until hungry enough to do that again. See my free carnivore guide: https://tiracole.com/carnivore-diet-getting-started-guide/
Discussion
In my guide and FAQs, I talk about what to do if feeling sluggish or tired, and point out that they may not be eating enough. I believe I have that covered, but will be revising soon to make sure.
That's great. Sadly people tend to not follow the guides - there wouldn't be a posts like that every week otherwise.
Improving marketing of guides would be great.