Well, if you want DAB to succeed - and I'd argue that those sales figures, with analogue radio still outselling digital, suggest it isn't really - then I think you do have to come up with some sort of plan to improve it dramatically.
That means addressing the shortcomings of DAB, which can either be done by allocating more spectrum so people can broadcast with better quality, and not be priced out of the market when they wish to do so, or by switching to DAB+ to offer the improvements in the same spectrum.
At some stage, in TV, we are going to need to do a switch to DVB-T2/H.264, even for SD channels, because of the squeeze on spectrum. That's why there's a temporary HD mux, to provide an incentive for people to get equipment that's compatible with that.
Something bolder should be being done with DAB+ in my view. Not just one mono station, but a whole load of them, providing people with a real incentive to switch over. Not necessarily over night, but a clear statement of a phased timetable.
So, for instance, if the new mux was all DAB+ with content you couldn't get anywhere, wouldn't that be a fairly compelling reason? People with older sets would continue to get the existing DAB stations. Over a few years, some of those would convert to DAB+, with the BBC channels probably being the last to go - possibly with a DAB+ Radio 3/6 Music to help things along.
At least that would be a plan. Which, I think, would be a damn sight better than what we have now. Surely we can't just keep saying "think of the first generation sets" indefinitely? There were quite a lot of first gen Freeview boxes and TVs that fell by the wayside over things like the change to 8k; those generally cost a fair bit more than a DAB radio.
If we just keep on as we are, a lot of people are never going to see the point of buying into digital radio.