Could the Cruise-Efficient STOL configuration be as efficient as a conventional airliner?
Without data, it is not possible to tell if one design will be better than another. This is because it is one thing to make a concept (which this is) and entirely another thing to manufacture and operate the aircraft (like A320/737).

Actually, the design in the video is not entirely new, It is similiar to the Boeing YC 14



developed for UASF AMST program. It is instructive to note what happened in that program.

The AMST program was initiated for developing a tactical STOL aircraft, requirements similar to the CESTOL. Even though YC 14 met the requirements, the program was scrapped for other reasons and the C17 was developed from another contender in AMST program, the YC15.

Even during development fo the YC14, the drag was more than expected and Boeing struggled to bring it under control.

However, I doubt the design as shown is ever going to be made into an actual aircraft. There are too many problems at first glance


The wing seems to pass right through the fuselage. This is not going to work in a transport aircraft.
The location of the engines suggest that the main spar will pass right through it. This will have strength implications.
In case the aircraft is used for STOL operations, the rear fuselage design should be redesigned for preventing tail strike as the landing gear in all probability will be shorter.
Putting the engine inside wing is not a great idea as it increases complexity and chances of catastrophic wing failure.  


There are a number of similar programs for developing efficient STOL aircraft, none of which have come into fruition. It is going to to be the economics of the operation from small airports, rather than the aircraft itself, which will decide if these designs will ever see the light of day, let alone operate in commercial routes.