For home applications, either Internet radio or Sky digital offer all the radio one could possibly want.
Whereas in the car, the requirement is for nothing more 'geeky' than RDS radio. Remember when that was first launched with all sorts of options? No-one bothered with them and only station name and automatic tuning are really needed.
For traffic broadcasts,
local radio tells you what's happening near to you and TMC on your GPS gives you the national picture. It's all very nice to hear the Radio 2 weather-wench yakking on about snow on the M74 when you're down in British West Oxfordshire, but it's rather an ineffective method.
Before GSM phones or RDS and TMC, I used to have a CB. Not so that I could go "One Nine for a copy", but to ask about the traffic. A 'westbound eighteen-wheeler on the M4'....OK, probably someone
pretending to be one
, once gave me the heads up about a "Fender bender on the eastbound superslab", meaning an accident on the M4, so I took the next exit and went cross-country. So I met my ladylove at the airport on time!
That's what I want car radio add-ons for, to provide useful information! Not to tell me about high winds in the Highlands 500 miles away, or ducks crossing the road in Little Piddle on the Gusset. Yet another facility which the useless DAB fails to provide.
Mind you, it was fascinating to hear the San Francisco traffic news on SiriusXM when I was in Ontario.......
DAB will be yet another geekology failure, I predict. Like Rabbit phones, OnDigital, Betamax, 8-track tapes.
Whereas VHF/FM...............works just fine!
Another feature of DAB is digital dropouts. Instead of a bit of hiss and crackle in weak areas as the signal reduces, you g t irri at ng g ps in tr ns mi ons..... Which the human ear/brain finds far less acceptable than a slight increase in background noise. Digital is, by its very nature, far more artificial than analogue and needs a very robust signal with complex error correction, plus a good bit rate. Even if DAB had all that, just what conceivable 'killer application' benefit is it supposed to offer which VHF/FM doesn't?
Edited to push that DAB radio advert off the side!