If transponders were invented today, they'd have video displays and show tv. But they can't be reinvented, because the government must start the ball rolling, and they really do not have any incentive to care.
The amazement of our aviation system is how the governmental agencies that are empowered to approve things have simply chosen to ignore progress in favor of constance. Since all aviation electronic devices must arise when a civil servant agrees to them, and the economic incentives of better operations are not at all in the civil servant's charter, we are saddled with nav, com and surveillence equipment and procedures that are the product of the same minds that run the post office.
While Fed EX trucks can tell their dispatch where they are within 10 yards, we have transponders and radars that are not accurate within 3 miles (which then sets the traffic density standards for the entire national airspace system!) My FedEx package has better flight following than an airliner.