Post-Apocalypse: Back to the Stone Age

[Ji ji]

It seems to me, Jonas, that you are a bit too optimist, Jules Verne-style :D
Our technological world is build over hyper-specialization and ultra complex mansion network.

However, let's imagine that, after a total catastrophe, humanity can return to medium TL in few generation. We can follow a total different fantastic path to obtain a TL1 world in near future.

In 20xx, a devastating pandemy strikes humanity. It can be a failed experiment of bacteriological world or anything you like. The disease kills everybody is infected by it. Everybody but 4 years (or less) old.
We can imagine that only a few of older survives to first months. However, there are enormous stocks of food long lasting in warehouses and shops, buildings to protect themselves (in a world with few or no predators, like USA or western Europe), cloth to cover themselves and so on, and somebody manages to survive. So, let's imagine that, over 1% of population (4 years old), only 0.1% survives to reproductive age.
70.000 kids became men and women.

Among these survivors, nobody can read. Moreover, there is a very low density. They will develop creol languages. They lack technological knowledge at all. They cannot read, ignore writing basis - for instance, phonetic value of letters - and so books are written, to them, in an unattainable code and in a stranger language, that is likely to be never discovered.
After two generations, stories about previous world are already far legends and myths. After six generations, they are a new simple religion. With the total loss of technological skills and the total impossibility to decifrate the least bit of information, they're returned to TL 0-1.
A stone age society in a world of wonders, remains of what is called "the god's era" or so on.