That's because most of the time (if not all the time) the in-camera histogram is more conservative so to say and shows highlight clipping where there's no clipping (or less clipping) in raw.
Bigger zebras or bigger spikes in the histogram doesn't mean there's 'more information'. It's actually less information than in raw histogram.
i would suggest you learn how to set your camera up correctly. but then again you might be shooting an old camera and not have the functions i have on my a74.
Not to railroad your thread Jim. but there is no way in gods earth you could get the accuracy shooting raw with any method that would match my a74 using the zebras even if you had a computer plugged into your camera. shame i havent my field monitor. i can move the camera spot metering millimetres from left to right and fine tune exposure to infinite of a stop not just 1/3rd. . in fact the movement of the camera as i press the shutter button can change it 😀 the deleted members camera set up from the other thread is bang on. what im posting is not new, sony uses have been setting there cameras up for a while with his numbers.
There are a few ways to make Sony zebras more accurate, within 96 to 98 % of saturation for regular scenes, one is to set the camera to HLG with zebras set to 100+, the other is to use highlight metering with zebras set to 108+ or 109+. It's widely known among Sony shooters.
Which jpeg picture style are people using to shoot their raw files with? This makes a very big difference to the histogram & blinkies/zebras when adjusting settings when shooting raw.