DRM is certainly used on HF, and there are probably some DStar gateways on HF for hams.
Marketing DRM is somewhat problematic because there isn't a great deal of equipment that is already set up for it. There are, I understand, a few portables, but that's about it. As I understand it, some countries use a version of DRM (don't quote me, but I think it's referred to as DRM+) on their broadcast FM stations. I understand that it's quite popular in Europe because of the fidelity is so good. However there may be some country specific rules about where it can and can't be used.
For the Kenwood that was rather unclear - are you thinking of IDAS? That is an up and coming mode here in the States, but on VHF frequencies - never on HF. I couldn't even guess why it wouldn't be used in Europe...Mike