I’d recommend getting a Hisense Android (or Google) TV since they let you set it up without creating an account, then use “adb uninstall --user 0 …” to completely debloat it (including removing Google apps). Then you can use your router to block internet access to the TV’s MAC address, along with setting the TV’s DNS server to 0.0.0.0, which will redirect all DNS traffic to a black hole, effectively blocking internet access.
Also replace the launcher with LeanbackOnFire and the keyboard with LeanKey Keyboard while you’re at it. Note that replacing the launcher will block the Input button on the remote from working, but LeanbackOnFire will allow you to access the inputs from the homescreen. You can also use Button Mapper to remap whichever remote button you want to whichever HDMI input you want using an Android broadcast signal, but that’s a bit more advanced and requires reading adb logcat logs to figure out how to switch inputs using the proper command.
If you’re feeling super adventurous, you can dump the boot.img using UART in the Uboot bootloader and root the device after unlocking the bootloader. Note that you will need to enable UART in the service menu before unlocking the bootloader since unlocking the bootloader will make integrity checks fail (including certain DRM), which will also make the service menu inaccessible.
Additional note: disabling Google apps will make the stock launcher stop working, so you will need to install a replacement launcher before debloating.
I’d recommend getting a Hisense Android (or Google) TV since they let you set it up without creating an account, then use “adb uninstall --user 0 …” to completely debloat it (including removing Google apps). Then you can use your router to block internet access to the TV’s MAC address, along with setting the TV’s DNS server to 0.0.0.0, which will redirect all DNS traffic to a black hole, effectively blocking internet access.
Also replace the launcher with LeanbackOnFire and the keyboard with LeanKey Keyboard while you’re at it. Note that replacing the launcher will block the Input button on the remote from working, but LeanbackOnFire will allow you to access the inputs from the homescreen. You can also use Button Mapper to remap whichever remote button you want to whichever HDMI input you want using an Android broadcast signal, but that’s a bit more advanced and requires reading adb logcat logs to figure out how to switch inputs using the proper command.
If you’re feeling super adventurous, you can dump the boot.img using UART in the Uboot bootloader and root the device after unlocking the bootloader. Note that you will need to enable UART in the service menu before unlocking the bootloader since unlocking the bootloader will make integrity checks fail (including certain DRM), which will also make the service menu inaccessible.
Additional note: disabling Google apps will make the stock launcher stop working, so you will need to install a replacement launcher before debloating.