IMO it's worth watching the video rather than reading someone's writeup of it. My favorite part is this (written) list of everything that went wrong [1] ... and how much of it is due to the intersection of hardware, software, vendors, and linux
I don't even like carrying the smallest of folding umbrellas around in case it might rain. Then if it does, this thing will hover so far above and away that you get wet anyway optimistically saving up to 50% of raindrops. 50% wet is still wet. If I have an umbrella I hold it close over my head unless I'm covering someone walking with me.
Any wind speed above 20m/s is also going to just blow it straight out of the air or at best heavily reduce flight time.
And then there is the little issue with having a mini lawn mower constantly above your head: loud and dangerous.
Having said that, we can still applaud the creator for bringing their idea to life.
They should have used Apple hardware.