In general, studies I've looked at show that even with unequal consumption, even those in the "high consumption" (and therefore probably higher fluoride ingestion) don't lead to what would be considered an excessive amount over the recommended exposure limits. Not saying it couldn't happen of course, there are outliers. Overall exposure should be considered for children.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2697936/
> The probability of exceeding the UL of 7 mg fluoride per day via a normal diet was estimated to be very low in the Belgian adult population.
Note: it's hard to find studies like this that focus on kids and not adults, but except for the difficulty in getting accurate responses from kids, that shouldn't lead to a difference. However given that the upper level is lower in children, it's a much tighter window that could then be exceeded by other sources of fluoride like swallowed toothpaste or food supplements with fluoride. So caution is probably warranted.
An Irish study found no risk of excess consumption by adults or children (excepting "misuse of toothpaste"):
- https://www.irishtimes.com/news/health/fluoride-in-food-drin...
- https://www.fsai.ie/publications/total-diet-study-2014-2016-...