True, but you didn't have to replace your TV, just add a cheap set-top box. (And not even that if you had cable or satellite TV.)
Also, at the time, most people only had one or two TV sets.
With DAB, you have to buy a new set, and most people have multiple FM radios: typically living room/hi-fi, kitchen, bedroom alarm clock/radio, car radio, boomboxes, and FM radios in smartphones and MP3 players.
We have about a dozen FM radios at home and there is zero chance of us buying any more DAB radios than the DAB/FM/CD "kitchen radio" we already have....
The obvious option is to buy a DAB receiver that broadcasts an FM signal to all your existing radios. That's how some of the DAB "radio adaptors" for cars work.
UI for digital radio requires a more expensive hardware than for TV set top box (which will be happy with just the antenna in / signal out and power interfaces, and a remote control).
It's not like anyone was asked when digital TV was the only thing left working..