I saw that and it is not a jet in today's parlance of what most pilots would call a "jet". Hell, it looks like there are 36 extremely large brushless outrunner motors.
From an engineering perspective, if something produces thrust primarily by producing a jet of surrounding matter (water or air) and taking advantage of Newton's third law, I'm not sure I see the issue. There's no exposed airfoil, and it doesn't appear to care about Bernouilli's law (except for lift).