I wouldn't be surprised if you didn't have some code for looking for undersecured networks capable of being exploited to derive credentials, though at least then you'd have grounds to sue under CFAA.
I have an old Vizio and 2 Samsungs. Configured them wired to updated the firmware then blocked the port on the switch. I use an AppleTV for everything as I know what it is sharing.
Bandwidth is much more limited so it probably won't send screenshots of what you're watching like has been reported with some TVs. Screenshots aren't really needed, though, when there's a host of other metadata and on-device processing available.
A destructive approach would involve desoldering the chip or unplugging the antenna. A nondestructive approach would involve Faraday-caging the television: a mesh or aluminum foil taped around where the antenna resides.
Also, what are you "unusing" it for exactly that requires it to have power?
[1] https://www.reddit.com/r/VizioTV/comments/96gtti/vizio_tv_us...
[2] https://www.consumerreports.org/privacy/how-to-turn-off-smar...
The uploads to downloads look like P2P.
Not sure why it'd be asymmetrical though if you aren't managing it and what would it be storing on at that GB? Is there a hard disk in the TV?
Are you totally positive and 100% sure that this is even Internet traffic? Unifi will report all LAN traffic too. Some of those first gen smart TVs will spew untold amounts of multicast and broadcast in an effort to discover DLNA servers and other media devices.
Anything other than speculative theories?