Why has my LG (lg-65UF9500) screen gone grey with some static?

Why has my LG (lg-65UF9500) screen gone grey with some static?

Last week, our lg-65UF9500 screen went to all grey. The power on/off works, but no other functionality is available. We are trying to determine whether it is worth having it serviced vs buying a new TV (which will not be an LG given that this TV was far too expensive to go down like this after 3.5 years).

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