I mentioned it in another comment, but it's to prevent the case where the TV might be connected with an ethernet cable in the future by someone other than me, giving it an opportunity to upload any collected historical data it might have.
I'm not actually very worried about that happening, but I already had the thing splayed open so I figured I might as well just gut anything I could get an iron to and didn't plan to use.
They (Android based Smart TV's) often have USB ports and various means of installing your own sideloading software | dropping back to command shell as admin, etc.
While firmware updates can be applied that way, here's hoping for a future OpenTV OS with all the desired features and none of the bolt on merchant wares.
I don't think the TV can electrically tell the difference between the ethernet port being soldered in or not. Removing the wireless NIC was the only thing I was concerned might cause some broken behaviors.