What you are overlooking is, of course, the thing that virtually everyone wants to overlook--racism and exploitation. The variant here is that the hero is being made into a celebrity, not a serious writer; Mory's character comes to know that, and, in keeping with the passivity that is one response to alienation, goes with it. And it leads to a series of highly ironic developments. Of course, the French (as with nations that practiced a very structured form of colonialism for more than a century, as opposed to the ham-fisted Johnny-come-lately "ugly American" variant...) showed much more "savoir faire" in their exploitation strategies.
(The above discussion could be expanded, but it makes people very uncomfortable, suggesting that this aspect of the story is "dated"--a particular kind of "enlightened," cynical nonsense that afflicts white folks on all sides of the political spectrum. Drach calls all this out by showing the psychological damage for what it is--the suicide attempt is a way of addressing the various, often paradoxical responses to alienation when the oppressive conditions overlap. Even overt acts are rendered passive and ineffectual, rendering life (or death) in terms of the absurd. In that regard, Drach is following Yves Allegret's approach--what I term in the (upcoming) book "absurdist existentialism."
The soundtrack is superb in its range of color within strains of jazz; it is tailored to the shifting ground of the story. Its looseness and divergence from either "cool" abstractions or "hard bop" insanguinations keep the story from getting too dark too soon--the ironies need to accumulate before the story and the soundtrack become ominous.
Drach would meet and marry Marie-Jose Nat right after this film and his approach would eventually merge into that creative/romantic association. His playful use of form that is his signature here will recede into a more orthodox alignment with sixties French filmmaking. He made a number of worthy film with her, but nothing else ever had the startling convergence of elements we see here.
It was our great privilege to bring it back to a film audience...
Philippe Mory went back to Gabon (born there in 1935), where he was the prime mover (originating screenwriter and lead actor) for one quite interesting film, LA CAGE (1963), with Jean Servais and Marina Vlady (which we've managed to get hold of and will roll out one of these days: it was a bit far afield for FRENCH 6, where it needed to play with a film dealing with other aspects of colonialism). After that, he remained in Gabon, became involved in what we might call "cultural politics" and is credited with developing the Gabonese film industry. A final irony WRT to ON N'ENTERRE PAS LE DIMANCHE--in 2016, aged 81, after a terminal cancer diagnosis, Mory committed suicide.