The "digging" is being done by..."The Marketplace." As in: digging a GRAVE.
Receiver manufacturers? They're done. Retailer electronics outlets? They've been burned. They won't be back. Broadcasters? The ones with sense - which would be, according to iBiquity and more reliable sources, about 83% of FM and 98% of AM operators - have said, hell no. Listeners? Assuming you can find someone who even knows what HD Radio is, they don't care.
Just shopped for another car this weekend with a friend; she bought a Honda CR-V at a dealership which also features Mercedes-Benz vehicles (HD is available on the Benzes as part of entertainment-nav package groups which list for $3900 to almost $8000.) I asked the salesman about HD Radio, and got the usual: "HD?" "What's HD?" "You know, DIGITAL radio." "Oh, you mean XM-Sirius....."
Honda does not offer HD Radio in any model.