It's more that it's a completely different technological paradigm. 2G is deeply based on ideas of circuit switching, not just on the radio link, but also in the core network.
It's possible to emulate all that at various levels, but that doesn't come for free (in terms of complexity, hardware, and spectrum). Maybe in 10 years it'll be cheap enough that it'll just be done in the spare cycles of some 6G or 7G SDR network, though, if that's worth the extra spectral inefficiency.
It's possible to emulate all that at various levels, but that doesn't come for free (in terms of complexity, hardware, and spectrum). Maybe in 10 years it'll be cheap enough that it'll just be done in the spare cycles of some 6G or 7G SDR network, though, if that's worth the extra spectral inefficiency.