In a text-only network for instance somebody could take an image file for instance and encode it as text (hex dump, base64, etc.). For that matter in the 1970s people would print “images” using text characters on a line printer and although mainframes are said to have ‘no graphics capabilities’ you will see plenty of EBCDIC art on 3270 terminals.

If you had no privacy all the above behaviors could be punished but with privacy you can’t really stop people from using a network the wrong way. This model used for networking is quite flawed

https://en.wikipedia.org/wiki/OSI_model

but brings out that networking can be seen a number of distinct concerns and that the content you send over it is distinct from the transportation.

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https://en.wikipedia.org/wiki/Automatic_Packet_Reporting_Sys...

which would be impractical to send multimedia content over because it is low performance and would be dismissed out of hand by ‘cypherpunks’ because privacy is forbidden by law. So is using it for e-commerce.

All kinds of networks are possible, but networks have ‘network effects’ such that the value that people get out of a network is an increasing function of how many people are attached to it. Even networks compatible with the present internet such as

https://en.wikipedia.org/wiki/IPv6

because even informed people will hesitate to spend time or money on something that only has hypothetical benefits to them.

Nothing stops you from forming a network with a small number of friends except for the practical aspects such as having a physical connection. If you are close in space you can maybe use a radio link like WiFi or runs wires but if your friends are in another city your best bet is to make an

https://en.wikipedia.org/wiki/Overlay_network

which lets you impose your own rules on top of the economically viable network we share. Since most of the cost of internet service is ‘the last mile’, a connection to your network is going to cost around $40 a month when a connection to the internet costs $50. Few people are going to decide the new network is so good that it replaces the internet so it is a matter of adding a $40 bill to get access to sending text with a few people and having access to an honest but understocked store. The cost to create that store is the same as creating a store that serves thousands or millions more users so it will either not be invested in or pass costs on the users. Such a thing is exclusive, not inclusive, by nature, although that may be the point.