There should be a ham radio version of the internet.
Didn’t usenet used to be a separate entity?
Still is, but you now pay for the service.
Usenet was always internet based (if you also count its precursor, ARPAnet).
It is possible to route TCP/IP over Ham radio on various bands using packet radio technology; this was being done already 25 years ago. Therefore, hooking Ham radio LANs to the internet was possible in principle. However, the bandwidth was too low, IMHO, to be useful.
A possible future apocalyptic scenario could see nets using unauthorized low-power short-hop point-to-point microwave links. There would have to be adaptive routers to handle the constant appearance and disapperance of the nodes in the network.