I feel similarly. I only used Ondoyé as a "name" replacement because it was written that way in the original records. The original records are written in a specific formula, just like how we on WikiTree have a formula. The priests at the time chose "Ondoyé" to occupy what we would call the "proper first name" field in their own records, so I thought we should respect that. I also figured there was a practical reason--if you are searching a database of original records, or a transcription of original records, searching for the name "Ondoyé Langevin" will limit your results and help you find the person you're looking for.
But over the current rule, I would prefer a solution where all French-speaking unnamed infants could be called Anonyme, because I feel that adheres most closely to WT's policies. I also feel really awkward about changing existing Anonymes to "Unnamed Infant." For example, the difference between the children of [[Jobin-121|Jean Baptiste Jobin]]:
Currently: Victoire, Joseph, Julie Célina, Joséphine, Denise, Marie Adélaïde, Onésime, Anonyme
Changed to: Victoire, Joseph, Julie Célina, Joséphine, Denise, Marie Adélaïde, Onésime, Unnamed Infant
I can certainly put up with it but I don't especially like it.