It's been a while for me (I don't upgrade things that work and I try to buy things that last a long time...)
But, Hotel Mode might still be a thing, and it might bypass some "smart" stuff on the TV
I used that to make my TV start on the correct external HDMI port for my MythTV instance running on Arch Linux (btw) with dual TV tuners in.
The TV is rarely used to watch live TV and it's certainly not connected to any networking.
Just another approach that I've not seen mentioned here