Because the article is very misleading.
Smartphones MAY have a chip in them that is capable of receiving FM transmissions [probably as part of the Qualcomm/whomever chip for processing cell phone signals].
But not a matter of 'just turn it on' and everything magically works.
You need an antennae/other external hardware that receives those signals properly. I'm not an antennae engineer,........
Since I have some phones that have the FM radio enabled all that is needed is headphones.
The antenna is the wires of the headphones.
That is not to say that the pin for the antenna is connected to the headphone connector.
It is also not clear what the regulations domestic and international are for testing the
FM radio for unwanted interference and matching the national band allocations.
But the original question is interesting. Local radio is invaluable in a disaster. The power budget
and infrastructure (transmitter towers) for FM radio are much more available. The service area of
a single FM radio tower could cover hundreds if not thousands of cell towers. Cell towers also depend
on digital backbone and data connections (routers) that also need uninterruptible power.
Local emergency management need only contact the radio station and the radio station only needs
a single generator. Radio is part of the emergency broadcasting system and disconnecting the FM radio
is disconnecting the EBS.
Having said this I recall waiting on the local FM radio station to announce school closure on one
especially nasty blizzards winter morning. There was no announcement... the school system could
not connect to the station by phone and the roads were so deep in snow that direct contact was
Legislatures in earthquake, tornado, blizzard, hurricane disaster risk areas (the entire US) should
be paying attention to this. Because of the EBS link your representatives should be demanding internal
communications that fail to enable this important service. Disconnection and de facto dismantling
of the EBS in favor of pay for service revenue should be blocked.
Then there is: "As Radio.no notes, Digital Audio Broadcasting (DAB) will provide Norwegian listeners more diverse radio channel content than ever before. Indeed, DAB already hosts 22 national channels in Norway, as opposed to FM radio’s five, and a TNS Gallup survey shows that 56% of Norwegian listeners use digital radio every day. While Norway is the first country in the world to set a date for an FM switch-off, other countries in Europe and Southeast Asia are also in the process of transitioning to DAB." (gizmodo-dot-com)
Thus I also want DAB support in future phones...