That was never implemented in any devices and is now a vestigal limb of the HDMI spec.
Ah, the obligatory “but ETH over HDMI!” It doesn’t need to be “considered” because it doesn’t exist outside a spec.
And it’s clearly less convenient for exfiltration vs most other options. Even closed implementation of HDMI eth to a soundbar of the same brand: then where to
Yes, that’s my second argument: even if it were implemented, you think Apple’s going to let just any ol’ POS IoT junk use an Apple TV’s connection? “Pass through using my IP address doing $DEITY-knows-what? Sure, random device, have at it!”