Aloha!
The digestive tract, jaw and other features of humans have much more in common with herbivores than with carnivores - so it is clear to me that it is easier to make the case for us also being primarily herbivores than for anything else.

The issue with protein/carbs is that the 'recommended' amounts for daily intake are not necessarily entirely accurate or appropriate for everyone and so if we want to have significantly lower carbs, we probably need to go much higher with protein - which isn't really an easy thing to do - just going by the numbers - but it can be done.