In Debussy's Arabesque #1, mm. 6–7 (among others) are scored as triplets against eighth notes (quavers):

(Image Source: IMSLP, first edition)
I've always interpreted this rhythm literally, and that is what I've heard in recordings and performances.
However, I came across Debussy's own recording (below), and, short of a painstaking transcription, it sounds more like "right hand as written; left hand arpeggio ad lib." I was left with the impression that Debussy intended this to sound more improvisational, and just notated the "impression" (for lack of a better term) of the sound he imagined.
I'm interested in what scholarship has to say about Debussy's attitude in this regard (literal interpretation vs. improvisation), either specific to this piece or regarding his compositions in general.
Can an improvisational approach to Arabesque #1 specifically, or Debussy generally, be justified by what is known about Debussy's attitudes toward the piece, his music, and/or music generally?