If 50% of the population doesn't have a digital radio to listen to in the car, I'd say it's too early to switch off, unless there is a really compelling other use for those frequencies (there isn't really), or the broadcast cost is very high (it is quite high, but no higher than it has been in the past).

“The transition, which began on January 11th, allows for better sound quality, a greater number of channels and more functions, all at a cost eight times lower than FM radio, according to authorities.”

I'd take the "better sound quality" claims with a grain of salt, absent information on codec and bitrates.

It's not about the codec or bitrate, it's about error recovery. The scenic Norwegian mountains are not kind to radio transmission.

FM fidelity was achieved by building one transmission tower per 2000 inhabitants. At a guess, FM is really being switched off because noone wants to pay for all those transmitters any more.

The process of digital audio quantization is inherently lossy - https://books.google.com/books?id=nc-fBwAAQBAJ&printsec=fron...