What is particularly astonishing is who published these:
Fortress is a stalwart Christian academic press of great renown, usually known for publishing "belief-friendly" work — it is literally owned and operated by Evangelical Lutherans (although granted, they are more liberal than that sounds).
Meanwhile, Cambridge University’s renown and status need hardly be explained. That is as prestigious a publisher as any academic study could secure. Yet another study is soon to publish from Cambridge University Press arguing a similar thesis to these entitled, "The Letters of Paul in their Roman Literary Context: Reassessing Apostolic Authorship," by Nina Livesey.
So this is officially a mainstream trend, not some whack job nutcase spouting wild conspiracy theories "because he wants to sin."