I decided to do it in text form (optionally available as an audio recording) and split it up into multiple parts, to make it more manageable :)
The first part is out: The decentralization of the internet - Part 1 - What is decentralization and why does the internet need it?
The first part explains some of the problems with centralization and what decentralization at it's core means. The second part will have the more interesting overview of all the current decentralized networks and specifics on how they solve the problems or plan to solve them in the future. I'll add video clips to that one to show off the different networks.
Part 3 or 4 will go into the negatives that a decentralized network brings with it, especially when data becomes uncensorable and permanent. While I think the positives far outweigh the negatives, it would be dishonest not to mention them. Things like revenge porn for example would become impossible to delete, although it's already not possibly to fully get rid of something on the "normal" internet.