I would say don't throw your money on a dying tech, OLED. It hit it's peak at 600-nits and Panasonic managed to hit 1000-nits (HDR standard) with a whaky cooling tech that we're not sure if it's sustainable as it's just shown on CES 2020. 2020 TCL 8-Series (8K) and 6-Series (4K) will have 100% HDMI 2.1 support for gaming. Sony will have only one model that's mid-range will support all HDMI 2.1 features as leakers/insiders say, and that's XH90 (X900H), 4K. Samsung doesn't support Dolby Vision but the open-source HDR10+, and both probably gonna do that.
We should open a thread about what TV to pick when all consoles are revealed, I guess.