Ohh I totally agree if the show or movie is 4K then you should be able to stream it that way. The main point I guess I was making is be sure that the show or movie is 4K, some are not and if that’s the case it won’t work no matter what you do.
There is a list of them that support 4K.
https://hd-report.com/list-of-4k-ultra-hd-movies-tv-shows-on-netflix/
Their not wrong. Blue and light blue works for me.