I am unsure if this is the right community but here it goes.
I want to buy a smart TV and I will plug a HDMI device into it. I want to stream my games and movies to the TV via moonlight/jellyfin. I heard about ACR and how it can be used to recognize content running on our TV which will be then sold off to advertisement companies/data brokers.
Say I have isolated the traffic of the TV (the OS of the TV specifically) to a separate VLAN. But the connected HDMI device is connected to the internet. Can the TV use this network to effectively “phone home”? Do HDMI devices have this capability?
PS: I know modern HDMI dongles can also share data but I at least have the option to change the device/use a mini PC.
Edit: There might be a misunderstanding. I don’t want the TV to communicate via HDMI. I want to know if it’s possible and what should I do so that I can prevent this form of communication. However, it seems that this protocol is incredibly rare so I should be fine. However, some TVs can attempt to connect to open WiFi, so it would be wise to just yank the WiFi chip from inside the TV.


After verifying that OP’s intent was met I gave a more fun answer that abused the letter of what was asked.