Software NRSC-5 Receiver
github.com
github.com
The only reason this got rammed through in my opinion is that it allowed for DRM to be imposed on radio.
But there are some benefits which you didn't mention, such as including text & images in the broadcast for people without internet access, kind of like what Microsoft attempted a decade ago with FM subcarriers. There isn't that much bandwidth available for analogue AM radio either; using DRM would at least double that. And then there's the claim that switching to DAB allows for decreasing the output power, but I don't know if that really holds true in practice.
http://www.rtl-sdr.com/decoding-and-listening-to-hd-radio-nr...