Earlier quoted context omitted.
Technically we could build something like LoRa on the amateur bands. It's a pretty basic protocol with up/down chirps. With the kind of power we can use compared to the ISM bands this kind of robust protocol would have a huge range.
To some extent, modes like FT8 have shown how effective modern encoding techniques can be. The problem, I suppose, is that FT8 is ridiculously structured; optimizing to the core the bare necessities of a QSO. I think that is probably the reason for its success; if I want to talk to people, it's easy to find them on the Internet. But accumulating QSOs is an achievement in and of itself, and something you can only do w…
Have you looked into JS8CALL? It uses the same bones as FT8 but allows for longer exchanges.