Where are the reported cases of Reye's with willow?

ASA was manufactured for proprietary purposes, and adding the acetyl group actually made it toxic, hence the increased risk of Reye's syndrome that isn't seen in those taking willow bark as a febrifuge.

starches in kibble enhance oral biofilm production and increases caries risk - i know this as a long time dog owner that switched 20 yrs ago to a BARF diet; it seems obvious, but this is just anecdotal

Flour products and sticky carb-rich foods that stick to the teeth result in increased biofilm production, and the resultant shift in pH from bacterial acids causing degradation of the enamel. Fluoride works bc it is incorporated into the enamel, replacing hydroxyl groups in hydroxyapatite to form fluorapatite which is more resistant to bacterial acids.

edit: among sticky foods, this also includes nuts/seeds (and nut butters by extension, incl. legumes such as peanut), as evidenced by archeological evidence suggesting that hunter-gatherers that relied upon such foods had a high risk of caries development. In contrast, hunter-gatherer peoples that ate primarily animal produce had a low rate of caries development until the introduction of refined carbs.

I can see this is going to be very controversial, however, it is the elusive obvious. Fluoride isn't necessary if you avoid foods that promote bacterial adherence and the resultant damage to the enamel. This is something I have observed also in dogs and cats fed kibble vs those fed a BARF diet. However, if you eat a high-carb diet especially flour products etc that promote the development of bacterial biofilm, fluoride toothpaste at least is absolutely necessary to prevent caries.