This is a common problem, nest camera shows up and streams fine in the smart things app.
In the smart things TV (in my instance, Samsung Frame 2023), the stream is just a waiting/rotating circle and never actually streams.
Have read in the past that people have fixed this by downgrading nest cam stream quality to medium, however the lowest I can set the camera to is “high”.
Does anyone have any advice or know how I can submit a ticket to Samsung to get this fixed? Google have obviously washed their hands of it.