I work in a classified military space where the security of our equipment has been verified; our 80 inchers are all NEC and work wonderfully
When mounted in airports and the like, they are also mounted in environments where the lighting is usually such (i.e., much too bright) that nearly any screen (LCD or old CRT's) would generally appear "washed out". So the effect you see may not be the screens, but instead may be caused by the environments in which you generally see them operating.
Those cost way more than dumb displays did back before there were smart displays. Look at the 40-inch/43-inch models. They're like $800. I bought all my 40-inch 4k screens for under $300 in 2016.
The insane price gouging in these "professional displays" cannot be explained by advertising subsidies. We weren't paying those prices for equivalent-spec dumb TVs back when those were available for sale.
There’s of course a price difference between you $300 cheapo consumer stuff, and a $1000-2000 pro display.
I used to have these pro displays at home with Chromecast, works fine.