This is not entirely correct, Raytheon were going for a slightly higher frequency (2.6 IIRC) and the FCC ordered them down (forcing the recall of their trial ovens) because GE wanted to use crystal oscillators (klystrons) in the 1.2GHz range, and they wouldn't need to worry about the awful klystrons harmonics if they could bleed into 2.4.
GE moved to magnetrons shortly afterwards anyway, I expect they hadn't had the radar manufacturing scale that Raytheon did at the end of the war.
Anything to the story (urban legend?) I grew up hearing about the origin of the microwave oven being from sailors witnessing sea birds being cooked by the radar dishes on their ships?
Decades ago I did a job for Raytheon (S/W for an X-ray machine control.) The Raytheon guy that hired us talked about standing in front of one of those huge radar horns to warm up as a young serviceman. I didn't RTFA but I wonder if the history went back that far.
GE moved to magnetrons shortly afterwards anyway, I expect they hadn't had the radar manufacturing scale that Raytheon did at the end of the war.