Fibre doesn't pass easily, it tends to slow digestion while causing damage to the intestinal lining. This is why fibre is so often causal with various digestive issues like IBS and why digestive problems are the most common complaints among vegans. Second, meat digests almost completely. The proof of this is just how little waste is excreted after eating meat (or any animal food). The amount of waste will typically be less than half, and it will be more optimally formed which goes against a lot of the plant-based propaganda that says you need to eat fibre or you will have diarrhoea. This is simply wrong. Fibre is like a band-aid, if you're eating a terrible (plant-based) diet, you will have diarrhoea, and fibre is a way to try to mitigate this. Except it often means trading diarrhoea for constipation. Look up any ex-vegan interview and you will come across either diarrhoea or constipation and often both. All food "rots" in the colon but the problem is much worse with fibrous plant foods since there is far more waste that sits there for longer. I've been eating animal-based for almost a decade, long before the whole carnivore thing became popular. I don't eat any fibre or vegetables whatsoever, only a little fruit occasionally. I poop regularly daily, about half the amount I did in the past, and I rarely need to wipe much because it's very well formed. I don't fart or get bloated either. This is like the holy grail to a lot of people especially women who are forcing themselves to eat stupid modern foods and suffer in silence. It's all the fault of activist-scientists pushing lies about meat.