Because it’s pointless, every aircraft flying has everything important that is susceptible to interference, shielded to prevent exactly that. On top of that, every phone you buy in the US through “official” channels is intensively tested by the FCC before it can go to market to ensure its radios are operating within spec and won’t cause interference with other things, like airplane instruments.
Can I enquire as to why not?
Because it’s pointless, every aircraft flying has everything important that is susceptible to interference, shielded to prevent exactly that. On top of that, every phone you buy in the US through “official” channels is intensively tested by the FCC before it can go to market to ensure its radios are operating within spec and won’t cause interference with other things, like airplane instruments.