Quality of source is the issue with big televisions.
Also I am convinced Hollywood are basically anti hi res. Sure, Amazon, Netflix and co will tell you they are streaming in ultra HD, but the source is deliberately shot in the dark with soft lenses in just so many recent movies.
Many 1940s-50s Hollywood movies look way better on 100 inch plus screens than the majority of contemporary efforts.
It just indescribably sad.
That said, some contemporary stuff is irrefutably good.
I was watching the original Robocop movie on my 100 inch set up on Blu-Ray last month on an old disc I had stashed away. Not A++, but hey pretty impressive nonetheless. Decent cameras without silly filters work best.
Big screens are a blessing and a curse. When the source is great they are just so enjoyable. When not, it's really upsetting.
Well shot HD content eats piss poorly shot 4K as per the recent "everything is shot in the dark with no dynamic range" type efforts.
Wake up movie makers and celebrate picture quality like the advent of Technicolour did.
One obvious reason is set expenses can be reduced by a massive factor if you can't see them.