Looking at the regional impact (40% SK, 15% Vietnam), you can see how internet topology creates these concentrated failure zones. We've had to work around these when designing different region interconnects at a previous life.
Fascinating analysis of how DDoS scrubbing centers can unintentionally leak non-attack traffic, creating potential privacy issues. The BGP path manipulation described offers a great technical explanation of why legitimate traffic gets diverted. Good reminder that security solutions often introduce their own complexities and side effects.