Hmmm. I see one problem with this. The cost estimate is very pie in the sky. If all air transport does this then that is going to lead to massive delays. Having a kilometer thick chunk of airspace unusable is cutting out 4 usable altitudes. Those planes now crowd already crowded airspace above and below. Not saying it shouldn't be tried but we should be more realistic about the cost.
Maybe it's the cropping. I remember a lot more people being around him