It's also possible that the idea is not competitive. The article is not quite clear. If it were the case, then it would be irresponsible to continue to finance what amounts to a rather exotic hobby.
You are free to believe whatever you want. But your competitors are meanwhile out there shipping 8 MW installations (and bigger ones are in test) and I really don't see how Makani will ever compete with that in a way that offsets all of its drawbacks. Flying the mass of the generators, tethers, complex launch and recovery system, power transmission over exposed cables, frequent maintenance, lightning sensitive, hard to keep mechanically safe in a storm, puny little rotors, what's not to like?
I sincerely doubt that. It fails the KISS test on a lot of fronts required for scaling. Scaling it up would require kites the size of 747's, the single points of failure (the tether and the hinge) would become exponentially heavier as the strength of the cable would need to increase. By the time those two lines cross you will need unobtanium to stay aloft. It's a neat idea but it is - with present day tech - not deployable at scale with the degree of reliability expected from windpower installations.
Keep in mind that the nacelle of a regular windmill is already quite a complex beast, it has one degree of freedom less and can adopt to gusty winds by simply changing its pitch, there is no need to bring the whole contraption back down to the ground before the wind fails to keep it aloft. The only way you can keep the Makani kite aloft if the wind drops rapidly is by controlled descent and that in turn you can do only about as long as your cables are. Typical generators for 'serious' windmills weigh on the order of 30-100 tons, that's roughly the take off weight of a 737-800 on the high end.
Props for actually building it though, that part - even at the limited scale of the prototypes - is quite an achievement.
Plan B could be large vertical shafts drilled into tall mountains. Let the high altitude winds create the venturi effect (low pressure) to suck air up the shaft and have turbines in the shaft to generate electric power. Similar to hydro power the construction costs are significant but after that it's almost trouble free energy.
The transmission to the shore is a 'minor' problem compared to transmitting the power from the kites to the base station. Also, every other off-shore power generation installation shares that same first problem, there are good solutions in place already (HVDC / offshore grid extension).
Astro Teller is quoted in the FT article as saying: “Our estimate of the rewards for the world, the reward to Alphabet, and the risks and costs to get there . . . they change over time. It’s part of my job to assess that and make sure that we’re picking the best ones we can for Alphabet to spend its money on.”
