https://www.businessinsider.com/what-foods-looked-like-befor...
The idea of four guys going into the woods and spearing a deer is a myth, a false parallel to modern sport hunting. Beaters pushed the prey towards kill zones. Fires could be set to get game moving. Fences would be biult to funnel game. And everyone was involved in processing the kill. Sure, maybe the big guys threw the spears but that was actually a small part of the process. The safest kill would always have been that where the animal injured itself first, no big guy muscles required. So there were plenty of jobs for all abilities.
The same is true for agriculture. Even today, with all of our mechanical wizardry, farmers on the plains still pull their kids out of school to help during harvest.
Note that many early humans lived in "hot and relatively stable climates".
https://en.wikipedia.org/wiki/Buffalo_jump https://en.wikipedia.org/wiki/Desert_kite
https://explorersweb.com/hiker-discovers-iron-age-reindeer-f...
https://thecanadianencyclopedia.ca/en/article/northern-yukon...
>> The most technologically sophisticated is the caribou fence complex. Ten of these complexes have been studied by archaeologists in the northern Yukon and nearly 40 others have been recorded in adjacent Alaska. The oldest surviving fences date to the early 1800s, but oral history suggests fences may have been used for thousands of years; they were last used about 1910.
Have you seen non-tech office workers solving computer problems? Gathering around, hitting the case, pressing random buttons, calling their friends, who are also clueless, on the phone, everyone advising everyone else on what to do next? This is exactly how programmers and SREs deal with the same problems according to you.
Also tubers.
Or a knapsack of dried fatty meat with a fairly indefinite shelf life.