> for at least hundreds of thousands of years, to which they were extremely well adapted adapted evolutionarily.

Hundreds of thousands of years is not a really long time in evolutionary terms, and evolution doesn't necessarily, even given a long time, get out of a good-enough local optimum to “extremely well adapted”.

It's also debatable whether conditions in which humans evolved are really a steady state.

More to the point, humans being ideal for the conditions—what the argument from evolution suggests—is not the same as the conditions being ideal for humans.

I thought about responding to these critics, but they don't really say much beyond "you never know!"/"don't be too sure!", so I'll leave things as is.

Species don't change so that the conditions become ideal for that species, species change so that the species is (close to) ideal for dealing with that environment. This is a very important distinction. Certain plants may grow in the desert with very little water, but that doesn't mean that they don't grow faster with more water.

Ideal in the sense of "outcompeting the other animals of the time in terms of breeding". Far from ideal in the "I'd like to be happy" sense.

Didn't people in early Hunter-gatherer societies have drastically lower life-expectancy, height and IQ as compared to modern humans living in industrialized nations? Evolution may not value those traits all that much, but we certainly do.

True, but it's not like diet is the only thing different between their lives and ours.

I think violence, poverty and disease were the bigger factors.

All I'm claiming is that our digestive system is adapted to what we had to eat where our species evolved.

Umm, if you're gonna parrot vague evo-psych-anthropological arguments, they need to be more solid that this.