I can agree with the people saying flight wouldn't be the first thing people would try to perfect in this setting. Thinking from a realistic perspective, if I was thrown into the wilderness with nothing but some hand tools and my wits, in an environment where there was other people but no real form of law outside a few tribes with limited military power, what would I do? First I would need food and water of course. We have skills for that. Then heat and shelter. Of course we have those as well. Then a means to defend myself, my family, my friends, and our property. We have walls and weapons so check. So now that we have all of those what would I look for next? First a more reliable source of food than hunting and gathering. We don't have agriculture or livestock yet, so that would be a big priority. With agriculture comes stability and a tie to the land and something worth pillaging, so I need better weapons to defend my land with. Things like swords, spears, bows, traps, possibly even primitive firearms and bombs. I'm also going to need better tools to work the land. Things like plows, wheelbarrows or carts, etc. Once I have a steady source of food, a nice warm shelter, and am well defended. Then I can begin trading my surplus food for luxuries.

Paragliding is a luxury. It's something that a hunter gatherer society will simply be too busy trying to survive to build. People may want fun and excitement, but our ability to experience those things today is a result of surplus resources. We have waaaaaaaaaaaaaaaaaaaaaaaaaaay more than we need to survive so we can invest time into things like paragliding and video games.

The example is compare societies like hunter gatherer tribes in South America to societies like the Aztecs and Mayans. Aztecs and Mayans did amazing things, lesser tribes were lucky to have decorated pottery. Thats because Aztecs and Mayans had a strong agricultural economy driven by maize (corn.) I personally think that until we are able to grow some form of staple crop like corn, wheat, rice, yams, or potatoes that things like paragliding be put on the back burner in favor of skills more useful in a hunter gatherer society.

Not to say that it isn't interesting idea, or that we shouldn't remember it for an update in the remote future.