Every one of them on the market has a vendor-locked bootloader, so the answer is no. Best you can do is to use a mini PC or a RaspberryPi with Linux on it (there are alternative interfaces for TV).
You can also go with custom Android boxes that you can install ROMs.
So basically the best you can do is to use the smart TV as a monitor. Don’t let them connect to internet.
Every one of them on the market has a vendor-locked bootloader, so the answer is no. Best you can do is to use a mini PC or a RaspberryPi with Linux on it (there are alternative interfaces for TV).
You can also go with custom Android boxes that you can install ROMs.
So basically the best you can do is to use the smart TV as a monitor. Don’t let them connect to internet.