Whether the letter was written by the historical Paul or any other disciple of him, does not really matter. Karl Barth famously shared this position.

Some thoughts to Barth himself:

It is true that Barth could not have been what he was or done what he did without von Kirschbaum, and it is important to acknowledge her vital contribution to his work. However, when discussing and reflecting on the Barth-von Kirschbaum relationship—a vital practice for anyone reading or teaching Barth—we need to steadfastly refuse a logic that sees the harm of Barth’s relationship with von Kirschbaum on all parties involved as reasonable collateral damage for the “good” of the Church Dogmatics. The production of a brilliant piece of theology is never sufficient justification for harming others.

John Barth, Writer Who Pushed Storytelling’s Limits, Dies at 93 by [[Michael T. Kaufman]], [[Dwight Garner]]

We view the world in these simplified 2D representations of clearcut political entities. Fredrik Barth and Benedict Anderson have said quite a few important things about these issues of maps and boundaries.