As much as I like Sony, they have a major panel problem at this point. All their panels, TV and projectors are degrading. So I'd stay away at this point or buy a model that is known to be fixed. They've always had these issues from time to time. Back in the rear-projection days I had a 70" Sony SXRD, which had a major color shift after 3 or 4 years. Sony quoted around $1k to replace the optical block. I ended up buying a 65" Panasonic instead, which I gave to my parents 2 or 3 years later and bought something bigger.
Samsung is a good choice, so is Panasonic. For LG stick to their OLEDs, but be aware there's still a burn in issue if you use it as a everyday TV. If you're just using it for movies, you should be fine. Shadow detail is also so so and with every manufacturer, you're always playing the panel lottery.
If you don't need all the smart apps, check out TCL/Vizio if you're in the US. Their panels are top notch performers and give all major manufacturers a run for the money. TCL is the only manufacturer that can do around 90% BT2020 coverage on one of their models (not sure if it's available yet, they showed it at CES or Cedia, can't remember exactly).
You are aware that Dolby Vision is limited to 10-bit and static meta data right now, right? That's exactly what HDR10 does. The advantage of Dolby Vision is the ability to do 12-bit with dynamic meta data in the future.