Unfortunately this is not HDR. Maybe you have an HDR version but Youtube shows this as Rec 709. I knew as soon as I started playing it. If you check under Stats for Nerds on Youtube you will see its in Rec 709 with no PQ curve. I'm a certified Dolby Vision Colorist. Your file would have to be uploaded in Rec 2020 with a PQ curve (ST-2084) to be HDR on Youtube. Now, I have seen Youtube take several hours to display the HDR version, so it could be coming. To check your monitoring, here is an aurora time-lapse I did that is true HDR. Make sure your monitor is displaying ST-2084 HDR. Easy to find under display settings on a Mac computer.
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