It's a trade off I guess. I use Home Assistant to control TVs, so kinda need the access.

I believe LG doesn’t advertise such an api via Bluetooth

I could possibly do it via HDMI CEC, but I have a couple of Sony Bravia TVs that more often than not completely ignores that, so I prefer having control over assuming it happens.

I could see a threat if the TV had access to the internet and could establish a TLS tunnel or similar from the mothership, and execute commands on my LAN (or IoT network as it stands), and report back. That could establish a command & control channel that could potentially orchestrate an attack on my infrastructure via the TV.

However, reporting that "network X exists and has these devices" over a different network complicates things a fair bit. In theory they could still use the TV as a command and control platform, but it would have to switch networks between my closed network and the open network in order to execute commands and report results. Not saying it's impossible, just very unlikely.

Besides, the TVs are not alone in being cut off from the internet. I have two IoT networks, one for trusted devices (AppleTVs, Sonos, and the likes), and one for untrusted devices like TVs. They run on different VLANs, and anything on the untrusted IoT network can pretty much only talk to itself (client isolation) and the gateway, and there's no internet and no open ports to any other VLAN.