As the age gets lower, the benefits are harder to find. Easy decision for 70 year old male with comorbidities... not quite as simple for the very young and healthy.
Could argue both ways:
If it does not show harm, why not get the shot?
If it does not show benefit, why get the shot?
https://www.wsj.com/articles/should-vaccinate-children-covid-19-infection-natural-immunity-vaccine-mandate-coronavirus-11636384215