OLED - ROAMIO PLUS & Comcast "Picture Quality"

My PN64F8500 plasma is being replaced by an LG OLED65B6P and I've seen posts elsewhere that have been very critical regarding "Comcast Picture Quality" in comparison to whatever they were using as a display previously(LCD/Plasma etc). It seems most were likely connected to the Comcast X1 box.

My Roamio is connected directly to the display via HDMI with audio to a receiver. I don't use AVR pass-through. I had assumed that maybe I'd need to change to a newer spec of HDMI - I'm quite sure that...

OLED - ROAMIO PLUS & Comcast "Picture Quality"

OLED - ROAMIO PLUS & Comcast "Picture Quality"