Different bands have different physical properties.
One of the points of amateur radio is experimentation. Right now the old boys clubs that all ham radio organizations have turned into to have decided that packet networking isn't real ham radio and you shouldn't be able to do it on "their" spectrum.
Apart from talking to satellites, packets and encryption are fine there for some reason.
The UK band plans seem pretty progressive, explicitly allocating spectrum for digital modes, though it is admittedly still the poor relation to rag chewing:
(If you’re not familiar with the UK structure, OfCom is the FCC-like government regulator, while RSGB is the de facto ruling body / club-of-clubs run by amateurs for amateurs.)
