I want to have a planet similar to earth with 45% axial tilt when hunter gatherers have an advantage over agriculture. The only thing I could think of is far north(Siberia, Alaska) & Sahara desert, even there people keep animals (reindeer & camels) so I guess nomadic herding can't be completely eliminated.
What kind of features should planet have to make agriculture unfeasible while still being able to support life? I wan't a plausible explanation why farmers can't out-compete the hunter gatherers.
The lack of agriculture is due to being a winning strategy, not due to cultural reasons. If some band/tribe of humans could out-compete the others it would become a dominant one. The hunters will adapt or be driven off.
After thinking about the answers and reading this thread I believe that only Arid planet with Erratic rainfall could do what I want. But that planet would unlikely evolve complex life.
THINGS THAT I THINK WON'T WORK:
Magical things, reality-check tag excludes such things.
Undomesticable plants. If humans could live as hunter-gatherers they must have some food to eat. And some sources would be better then the other. Nothing prevents them to help the better sources to become more abundant. Sooner or later domestication will happen.
Undomesticable animals. We haven't domesticated American Bison nor Zebra, because we already have good cattle, why spend time on another one. If all we had is Buffaloes and Zebras I'm pretty sure that we'll find a way to have a herds of Buffaloes and that we'll bring them to pasture while riding Zebras. See this for recent example
Dumb apex predator. Humans dealt through history with many scary things check this excellent answer about Megalodon
You and I might be computer-bound bums with poor vision, but our ancestors were super-intelligent, awesomely effective pack hunters. No creature alive, from the a blue whale to army ants stood a chance against a pack of cave men.
Or even against T-Rex
Smart apex predator. I think this lead us to two intelligent species evolving on the same planet around same time, possible but very unlikely