The trouble is that no matter how hard you try, you don't really know how this physical infrastructure is configured. You buy from two separate suppliers etc. You can still have bad surprises.
Many years ago (1980s) the Internet as it then was had coast-to-coast redundancy, Boston-Seattle and Washington DC-LA (or something like that). Guess what... a train derailed somewhere in the midwest and cut both of them.
That said, this case does seem especially egregious.