The documentary Side by Side covers this whole topic pretty well. It’s basically about how digital technology has changed every aspect of the film industry over the last several decades. Lucas and David Tattersall are both interviewed, among many others.
Tattersall makes an interesting analogy regarding the criticism at the time that they were taking a giant step backwards quality-wise by choosing to shoot Ep2 in digital:
“You’ve got to lean back in order to spring forward.”
It does bother me that AotC and RotS will never have the same unified look as TPM, the OT and now the ST, but it was George’s money being spent on the PT and he didn’t want several million dollars going just towards scanning in all of the 35mm footage on the last two prequels like he had to do with TPM.