The Boring Company, a subsidiary of Musk's aerospace company SpaceX, has suggested that "fast to dig, low-cost tunnels" would alleviate the congestion issue in densely populated regions.
"It's a great thing if he can do it. The cost is really what he's up against. It really is incredibly expensive to dig holes under the ground," Moore said.
Uber, like Tusk's venture, has expressed interest in advancing the "flying car" technology when it launched its Uber Elevate project 2017. However, Uber's director of engineering for aviation and veteran of NASA, Mark Moore, hired by the ride-hailing company in 2017 to work on its "flying car" initiative, said Musk's endeavour was "one of the most expensive things you can do".
The Boring Company, also interested in the technology and the ecosystem, which would help avoid congestion, held a grand opening of a 1.14 miles demonstration tunnel in December 2018.
READ MORE: Elon Musk Showcases Long-Awaited Innovative Tunnel in LA (VIDEO)
The Boring Company has admitted the high costs of building tunnels, "with some projects costing as much as $1 billion per mile."
"In order to make a tunnel network feasible, tunneling costs must be reduced by a factor of more than 10," it said.
But while it proves costly, it is a feasible project to pursue, said the company, while "flying cars have issues with weather, noise, and generally increase anxiety levels of those below them."
Uber's Mark Moore, however, argued that Musk overlooked the latest aircraft tech and said Uber's aircraft will be 15 decibels quieter than the quietest helicopter.