Sharing my experience here because I didn’t know that this was a thing until a couple days ago. Bought a 17PM 256 and noticed the green tint when I would tilt the phone forward to reach the top of the screen one-handed. Straight on everything looks fine. My previous 15 pro would not do this, so I did the internet sleuthing which led me here.
I did the steps to find that I have a GH3 panel. I’ve since been able to compare the phone with two other phones of the same model. Both were GVC panels. The first I compared it to made it seem like mine didn’t even have a tint. It would turn the entire phone significantly more green at a much less forgiving angle than mine. The second I was able to try looked mostly the same as mine at a slight tilt, but further forward and mine would even out more, while the GVC panel had a stronger green tint more focused to the bottom 1/3. All felt relatively uniform and had consistent brightness with each other when held straight.
So by my own anecdotal evidence, I am much happier with my GH3 panel than I would have been with either of the GVCs.