I can't watch the video but I don't see what there's too regret unless you spent a lot.
Anything new that comes out will be cutting edge and cost an arm and a leg.
I found a way to get the 55 ks8000 for 1600 Can. And there's no way anything new will be that much better for same price
mainly for the HDR wars, even though HDR10 will most likely be the winner but there are talks that the next mediatek soc will support DV HDR, HDR10 + dynamic metadata and HLG. So presumably the if sony use that SoC next year the next tv will support all of those also. There is always newer stuffs coming out but changes can be huge or just incremental. Supporting all HDR formats is quite big for me, on top of that, the x850D replacement for next year will probably be much brighter which is good for HDR.