>From what I've read, life before agriculture was decent.
I've read arguments in both directions and I'm extremely suspicious that they are almost all basically politically-driven. It goes like this:
If hunter-gatherers are predisposed to more or less gender or economic equality, or certain social structures, then that should perhaps inform how we construct our own modern societies.
In order to escape the clear appeal to nature fallacy, it then becomes necessary to argue that not only were prehistoric societies constructed in a certain way, but they were also extremely well-off. Therefore we clearly must "reject modernity, retvrn to monke", and embrace True Human Nature embodied by some cultural tradition or ideology.
The exact inverse would obviously imply that we must embrace a certain idea of technological or social progress in order to escape the "natural state of humanity" as fast as we can.
However, was the human hunter-gatherer experience was ever all that stable or predictable such that we can obviously draw out either of those major conclusions? I think a decent null hypothesis might be that all the extremes of human experience and social structure had to have occurred to some degree and that the overall average and distribution would fluctuate quite a bit over time according to weather, migration patterns, and accidents of cultural evolution that humanity at any level had basically no control over.
I find it really hard to believe that we can possibly have enough evidence in any relevant discipline to rule this out.