You rendered 60 FPS .
At the Youtube Help page they say that 60 FPS isn't supported :(
That's not true.
I did a test here with 60fps, and it works with 60fps on YouTube. The only thing is that I uploaded it at 4K, and it still isn't in 4K. It's either still processing, (I uploaded it 9 hours ago) or it just won't work with 4K.
(I didn't stabilize the pitch and roll in that one. I did in all the next ones though.)