This is how it was seen during this period, and it does matters when we mention more settlers. Either you turn Louisiana as sort of Australia equivalent as it was attempted (and the problems it brings) or at the very least you try to change this perception. There's no much going around it.
I really disagree there : New Orleans was a fairly small city without an hinterland up to the XIXth. While it harboured refugees, it was mostly contingential to the Haitian revolution (something quite butterfliable with a 1770's PoD), arguably with other origins as well, and it provided little to no incitative about actual settlement for most of the XVIIIth century, while the colony was seen as an eventual cash cow without any real effort to turn it as such (arguably, the sheer cost doing so, when it was far easier to capitalize on Antilles...)
Americans, on the other hand, already began a more or less spontanous structuration of the territory after the independence, and had a real strategical but as well political interest on Mississipi which was ten times the economical artera it ever was for New France (if anything, you had a real rupture between Lower and Upper Louisiana). Louisiana without Canada offers little interest for France : at best it turns into a continental Haiti, at worst it's taken over by force which would be a walk in the park.
Strategical position isn't everything (or Gibraltar would be one of the main cities of Europe) : there's as well the economical and political background, and let's face it XVIIIth France couldn't give a damn about Louisiana except for embarassing fizzled projects (turning it into a quasi-penal colony, or the
Mississipi Bubble) and since 1713, it was increasingly dependent on Spanish good will. French Louisiana is a textbook exemple of a badly tought, planned and structurated colony, and it comes back to its establishment and frankly, it's almost surprising it wasn't lost in the late XVIIth century, maybe it would have allowed to relocate more seriously colonial ressources.
It was probably salvagable even in the XVIIIth, but it would ask for a perillous policy : such as definitely tying western Florida to Louisiana, admitting that Upper Louisiana in this context was a loss of everyone's time and ressources, and making it a de facto a Franco-American condominium hoping really hard iait wouldn't turn into an earlier Texas. Not litterally impossible : just very, very hard to enact from afar.
The IOTL situation isn't that relevent : the first immigration worth of notice was directly and indirectly due to French Revolution, in an essentially tripartite repartition (1/3 White, 1/3 Metis, 1/3 Black). Even from there, it as enough to provide with a strong identitarian feeling among the "old families", so to speak, which is the tree hiding the forest : between 1810 and 1860, with a demographical explosion, the massive part of the city was made of German and Irish migrants (that, arguably, tied themselves with the old inhabitants).