The best Smart TV is the one that is just 24/24 HDMI connected to your old Linux laptop with a GUI tweaked to act as a Smart TV with an air mouse as remote.
When I upgraded my desktop, I only needed to pickup a case and a few extra parts to have enough for a functional home theater PC. Running standard Fedora Workstation, controlled with Logitech K400+.
I stubbornly refuse to ever connect my TV to the internet.
