Even if that functionality is available on one of the multiprotocol wireless chips, adding even a tiny amount of support circuitry to enable may not be a wise move from a product design point of view.
In the USA, an FM receiver isn't going to sell phones. VR, better cameras, longer battery life, etc. sell phones.
Plus, FM receivers are much less power consuming than radio over data.
My next phone will have an FM receiver.
Not that I'm for eliminating the 3.5mm jack: this is just one among other reasons I'd refuse to get an iPhone even for free.
Would it be really so bad if someone made a smartphone that was ~2x as thick as an iPhone, with added battery life and usability?
Unfortunately, it's in these companies best interest to push a new phone every year, regardless of if the new features justify the added cost... or are even features.