I think the jury's still out about frontal damage:
https://www.science.org/doi/10.1126/scitranslmed.abf8396 https://www.medpagetoday.com/opinion/second-opinions/94301
As for children, yes, the risk is much smaller than for adults, but it's a moving target due to viral evolution, and why not reduce it as much as possible?
https://hms.harvard.edu/news/how-covid-19-causes-loss-smell
The risk to younger children is minimal.
https://www.nature.com/articles/d41586-021-02423-8