Youtube TV Low Resolution Help

I signed up for YouTube TV to be able to stream live tv and sports. I have a new Samsung LED and picture looks perfect 1080p on all apps like HBO Max and Netflix. No buffering. Works great. However, Youtube TV cannot stream an HD picture, it looks terrible and pixelated like standard SD tv before HD was a thing. The YouTube TV app has a setting where you can set resolution to Auto (where it chooses the highest resolution it can stream without buffering) or set manually to various resolutions from 1080 to 720 or 420 or even lower. If I set it manually to an HD resolution 720p, it will look beautiful but buffers and will not play normally. Its like the data is not coming through fast enough. But I have great internet speed at up to 75 Mbps and again have no issues streaming HD video on other apps. Just live tv streaming is the issue. This is my first time with streaming app for live tv. Is this normal? IS it the TV hardware maybe and I need something like a chrome cast or Apple TV? I connected the tv directly to the router with an ethernet and there is no difference between that and over wireless wifi. I dont want to have to go back to a dish for live tv... Any ideas or information to educate me would be very appreciated. Thanks in advance.

Edit- I see this should prob be in the tech forum, apologies