But in general, I think we know a lot less about the lives of people so long ago than many people (including academics) like to think. Research methods are often based on either assuming modern people's lifestyles are "just like" ancient people, or big leaps from extremely limited archeological evidence.
Grass-eating bison, aurochs, horses, goats, sheep, etc were our primary source of nutrition in the ice age, not to mention mammoths (as well as fish).
And this is evidenced by ancient cave paintings tens of thousands of years old depicting hunts as well as the bone remnants in the caves and homes of ancient humans.
https://www.newscientist.com/article/2115127-ancient-leftove...
https://blogs.scientificamerican.com/guest-blog/human-ancest...
But mostly what the conflicting theories with consensus that changes from generation to generation tells me is that it's very hard to know for sure how people 15K+ years ago lived.
Then there was a shift towards agricultural societies, where people relied on their plantations and domesticated cattle. I don't think the cattle meat would be enough for most of their meals, probably the most of them would be bread and soup.
This is just a vague recollection from A Brief History of Humanity, but it makes sense to me. Eating just meat sounds terribly "costly", you have to actively ignore all other sources of food around you.