I share your view - how does this article imply US companies and/or government involvement? If there were such involvement what aspect of BGP gives the US entities more ability to carry this out vs other nefarious actors? I ask this sincerely knowing almost nothing about BGP and wanting to learn...
You may have missed https://news.ycombinator.com/item?id=46504963 a few days ago where this same anomaly was discussed and American government involvement was directly implied by the article.