This whole article smacks of some CISSP pouring over BGP looking glass router logs and having a sophomore Eureka moment. BGP MITM is not practically possible because of the return path problem: the last router that dumped you the traffic believes you are the legitimate endpoint for that traffic and therefore is not going to forward it to the ACTUAL target once you're done doing nefarious things to it. The article tries to explain this away with the following:
"The traffic was likely examined and then returned on a “clean path” to its destination—all of this happening in the blink of an eye."
If the 'clean path' of the internet thinks Mallory is Bob, Mallory's theoretical egress 'Clean Path' will make the same assumption. Perhaps Alice's first hop AS was compromised? If so this is an isolated vendor network problem, not an 'internet at large' problem. Maybe Mallory's 'clean path' is a point to point to Bob? If so Bob's an idiot for signing a peering agreement with a known Hooligan.
This was likely a misconfigured customer router connected to an irresponsible ISP that doesn't filter the routes it accepts, just like the Pakistan/Youtube Incident. The author either doesn't understand the technical impossibility of the attack they're dreaming about or does and is willing to lose credibility in exchange for ad traffic.