Some of what I've read of Sartre's writing (some but not a lot) and your deft concise, focused and accessible exegesis / interpretation highlights a regrettable feature of existentialist and related thinking, which is framing the existential condition in negative or pejorative terms. It's as if they saw Nietzsche's "God is dead" theme as something to be depressed about, rather than to move on from.

My sense of Husserl (especially) and Heidegger is they were fairly accepting, neutral, and un-emotionally-colored about it, not dramatizing it -- as if to say "it is what it is" versus "woe is me." After reading your piece, I'm tempted to question how one can really be authentic or inauthentic in a life that is without meaning to begin with?

Could that be the start of what seems like Sartre's "confusing" if not confused attempt at a new morality?