I live near the ontario airport, went to pick up my brother last year, I had 5g signal. not a plane crashed. then again dont know if it affected any airplane. for what I understand it does as it was explained to me by another pilot.
semp
Semp, I was an airline pilot all my career. I don't think interference with the radio altimeter was ever likely to cause a crash. It was used primarily as an aid in the development of safe "low limits" instrument approaches. Prior to the development of the RADALT and other tools, the nominal limit on instrument approaches was typically 200 ft. and that was based on a barometric altimeter.
So in simple terms, if pilots have any doubt that their radio altimeter is not functioning to spec, they will not fly to lower limits (lower than the limit displayed on the approach chart that is based solely on the barometric altimeter).
So while I said that this issue was not likely to cause a crash, it's still a huge pain to airline managements as they either cancel flights or watch them divert from destination to alternate airports.