It sounds like ATSC 3.0 (promoted to consumers as NEXTGEN TV) is not well-established yet, and I would wait for another year before better tuners and more TV models become available. You don't want to sacrifice display quality, features, or price for a piece of new technology.
My next TV would be
OLED, which is
self-lit. I would steer away from QLED, ULED, LED, etc., as they are all
backlit LCD technologies, and none of them come close to OLED in display quality. They are the evolution of the old, awful rear-projector technology in some sense. LCD technology has remained because of low cost. Plasma technology used to be far superior, which was now replaced with the even better OLED. Even CRT technology was better than LCD technology until it lasted. Both plasma and CRT technologies are self-lit.
You may not need an 85" TV unless you are watching it from far away. A 65" display is already huge. Displays too large can be uncomfortable to watch and can cause fatigue more quickly. It's not to mention that the price increases a lot with the display size.
There are few LG OLED ATSC 3.0 TVs at the moment, and they cost $1,000 more than for legacy ATSC TVs (~ $2,500 vs. $1,500 for 65"). Just wait for another year and the price will come down by $1,000. Don't waste your money and/or sacrifice display quality for a TV larger than 65" unless you really need it (long viewing distance).
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