Uhh, sometimes I need to get photos to someone like yesterday, so they can pick out the ones they want processed. No time to do a contact sheet. The out of the camera JPGs are fine for this purpose.
My Golden Rule is that everyone is fully entitled to their own workflow. There are no absolutes. Photography isn't particle physics.
Phil, if you are a pro school portrait shooter, pro sports shooter with a 1-hour post deadline, pro wedding or event photographer - OK. I get it. But from your post I did not discern that.
I have a friend that shot the NBA (Spurs) for 20 years and he sat under the basket and shot nothing but JPEG on the highest-end DSLR pro sports rig available at the time. He transmitted jpegs sized for the web to his editor who was sitting elsewhere in the arena. The editor picked the winners and sent them after a few minutes of work on the wire and they were on the web in 20 minutes with very little or no editing of the jpegs because they knew exactly what they needed and had everything set-up in camera to get the jpeg the way they wanted it for NBA arena lighting.
I have a friend who has the largest school portrait business in Texas. They have 15 photographers who shoot Fuji XT-4s and the lighting is all standard and their in-camera jpeg presets are all how they like them and that has been derived from years of trial and error. They shoot nothing but jpeg and have that down to a science (which is why they switched from Nikon to Fuji recently). The don't have time to deal with raw handling and editing. They get thousands of images posted in a day and have huge servers and processes to store all the images and sell them to parents on-line.
But I think you will agree with what I said about jpeg vs raw. Give me the raw for 3 minutes and I beat anyone's in-camera jpeg 100% of the time. That is not an absolute, it is just a teaching point when I have discussions with new photographers deciding whether or not to shoot raw and when discussing all of this nonsense you hear from novices and equipment sellers about jpegs being as good as raw.
But I enjoy post-processing. Some people don't. So, for them have fun shooting jpegs.
And with the amazing computational photography of these Apple and Google phones now.... Well, that changes everything. But right now, our higher-res mirrorless cameras cannot do that level of in-camera computational photography with their vastly larger sensors and exponentially increased computational power requirements that kind of instant output would require. But who knows what it will be like 5 years from now?
But still, from what I understand about your case, you were past any pro to editor deadlines and were just trying to apply a bunch of accidentally done edits to the jpegs and get those instructions into the raw file edits without redoing each one. I was just saying that makes no sense to me and I wouldn't do it unless I had to for all kinds of reasons. But if you had to meet a deadline and just wanted to instantly get those edits in the raws from the jpeg edits, if there is a way to do that it is beyond me except maybe a group edit or syncing the shots as you go. I don't know.
Hey, if you are a pro and have a workflow then do what you gotta do.