I think the bigger issue is not whether it has some efficacy, even if limited (which could be interpreted as a good thing), it's the potential for the bacterium to create a mono-culture, which would be objectively bad (remember, diversity is critical in populations, and for our oral health perhaps even necessary).
So not so much perfect being the enemy of the good, fluoride isn't perfect either, but it is good. This is potentially extremely harmful, and possibly even a source of something like a new AIDS pandemic...
I think the bigger issue is not whether it has some efficacy, even if limited (which could be interpreted as a good thing), it's the potential for the bacterium to create a mono-culture, which would be objectively bad (remember, diversity is critical in populations, and for our oral health perhaps even necessary).
So not so much perfect being the enemy of the good, fluoride isn't perfect either, but it is good. This is potentially extremely harmful, and possibly even a source of something like a new AIDS pandemic...