Stone age man would not have come across many other people. Possibly, a couple of hundred in total. I was once told by the geneticist, Steve Jones, that in his visit to central London he had seen more people on one day than an ancient man would have met in the course of his entire existence. Our 'stone age' man would have come across more trees in his life than we will, so perhaps there is a balance between encounters with fellow men and with nature that modern life has turned upside down. Many people are said to be suffering from nature deficiency and this could be contributing to stress and anxiety. Our society as a whole, however, seems not yet to have reached "peak inter-activity" - social media has created the scope for almost 24-hour-a-day interaction with other people, many of them new 'friends' or even virtual strangers. Those who take advantage of social media to inter-react for many hours each day are the gregarious ones and even less likely to visit woodlands.
But perhaps it's more like sex: people vary in their appetites. If you scale yourself and those you know on a 0-10 range of sexual interest you will see quite a wide range - with men often, but certainly not always, being higher up the scale than women. Maybe its the same for appetite for nature - some people want to be outside most of the time while others are happy with very occasional and brief forays into the world of forests and fields. For example I came a across a young couple recently who wanted to be outside a lot so they hid away in a yurt in a community-owned woodland in Switzerland. The weren't found for four years by which time they had established a primitive existence where they didn't see many people at all. When the authorities did find them they were moved on but they were at least helped to relocate to another woodland. These yurt inhabitants were certainly hardcore lovers of the outdoor life and probably near the top of the scale in appetite for nature.
Owners of small woodlands often tell us that they want to "get away from it all" and they visit their wood as an antidote to city life. This was a driving force for the few people who bought their own woodland forty years ago but it seems now to be gathering momentum, which could be because of the increase in urban stresses or it could be partly as result of another phenomenon which explains how people judge when something is worth spending time on. A well-known psychological experiment places one person on a street corner staring up at the roof of a building. With just the one person looking up, very few of the passers-by will copy and look up. But if you put a group of four people looking up, about half those walking past will have a glance up, and if you put fifteen or twenty people staring at the roof then most of the passers-by will join in. We judge what's worth considering by what others do and we apply a rule-of-thumb that if a lot of people are doing something it must be worth considering.
So paradoxically people may be using signals acquired from observing the crowd to deduce that it's worthwhile to find a way to get away from the crowd itself. And most people, once they own a woodland don't become total hermits but they try to establish good relations with neighbours and adjoining woodland owners - so people are seeking a balance between too much company and too little. For many of us owning a woodland and knowing a few neighbours is a sort of "just right" goldilocks solution - not too hot and not too cold.