FM Radio disabled at hardware level... Myth or true?

"The only model having FM Radio chip is D855 and the chip is removed/disabled (pins grounded, etc) in other models like D850, D851, D855 TR, etc".

Is this true? If it is not, than you should be able to listen to FM Radio with Spirit UL app in any model just by rooting or installing a custom rom on it. Right?

If it is partly true, which means some models really have their chip physically removed/disabled but some models have it disabled just at software level, what is the situation for D850 and D851? Chip is there and FM Radio is possible with these models just by rooting or installing custom rom ?

Thanks in advance.