If hunting and gathering was an intrinsically easy, we would all be hunterer-gatherers. There would have been no impetus to change.
In other words, that is one very incorrect hypothesis.
Even when the season makes food more abundant, there is still the impetus to hunt. People really really like meat, for one thing, and then there are the other products that animals provide (like leather for clothes and bones for tool). These products are essential for daily living as well as relations with other people, in the form of trade.
But food is exhausted after awhile, which necessitates movement. Either the gatherers must expand their search radius each time they go out, or the camp must move. Sources of water also shift, so that limits where they can go. As do the presence of other camps and known predators.
Gatherers, who tend to be women, can’t just leave babies at home in the care of others because they are nursing. This includes children who would typically be weened in our society, like four- and -five-year-olds. So these women are not only working in their search for food (digging for roots, filling big sacks of nuts, making mental maps of plants that haven’t bloomed yet so that they can be visited in the future, etc.), but they are also lugging around babies and keeping an eye out on the toddlers.
Back at camp, if the men aren’t hunting, they are tending fires (critical not for scaring off predators, but for keeping an eye out for them), making and fixing weapons and tools, and training youngsters. Hunting is an exhaustive effort that can take days and days.
At night, someone has to keep an eye out for predators. The camp is never totally asleep. People take turns keeping watch. That’s work.
The biggest difference between their lifestyle and ours is that we think work ends at a set time and then we can go “live”. In other societies, working is not limited to 8 hours. It is distributed throughout the 24 hours of the day, with some down-time in between. Also, there is no such thing as “burn-out”. Unless your relatives really really love you, a person who is “burned-out” is ass-out. Burn-out is a construct of 21st century Western Civilization.
Anyone who thinks hunterer-gatherers have an easy life really don’t know what the hell they are talking about.