unplug?
Consumer devices don't have detachable antennas inside. They're soldered on. You can undo that, but that's a lot of work to remove the back of the TV and who knows what else to access the wifi module.
It is going to be harder to sell a smart TV as "brand new" if it doesn't have working wifi, since almost all consumers will activate that the minute they turn it on. When that fails, they'll call Samsung, find out they acquired stolen property, and go back to whoever sold it for a refund. Unless it was sold out of the back of a truck, they'll get that refund either via their credit card company or Paypal.