FM radio was integrated in even smaller phones 20 years ago. And the tech to “decode the signal” is already present in today’s phones. FM are radio signals, just like NFC, Wifi, Bluetooth and cellular.
Not the same radio frequencies, not the sames technologies (analog vs digital). Those radio hardware are very specialized, and won’t work on frequencies or technologie they are not meant to.
Correct, not the same technologies. It’s a much simpler circuitry. Very specialized doesn’t mean very complex. A hammer is very specialized too.
I read somewhere that SoC boards on today’s phones still have FM tuning capabilities, but they just don’t use them.
I’ll try to verify that, though.
Edit: this link seems promising: https://www.makeuseof.com/tag/how-to-unlock-fm-radio-hidden-smartphone/