IXs, BGP, RIRs like RIPE, and the proliferation around the globe of access ISPs, all prove how decentralised the Internet is.
But if the point the article is trying to make is "all this content is being hosted in fewer and fewer locations and that's bad" then I completely agree. It damages choice and hugely increases the blast radius of service outages.
Now if Amazon and Facebook started offering end user connectivity, that's the time to really worry. cough Google.