-meat is not indigestible
-red meat only increases cancer risk when eaten in excess. Preserved meat can increase cancer risk, but that's not the meat, that's the preservatives.
- Meat itself does not create new diseases, it is the crowded factory farming conditions that lead to diseases.
-only excessive meat consumption leads to reduced beneficial gut bacteria.
You have made a decent argument for reduced meat consumption, or even meat consumption in a modern context.
Meat was important during our evolution, but evidence suggests that we mostly scavenged bone marrow and that it would only have been eaten about once a week. No where near as often as modern humans eat meat.