There is absolutely no good reason to vaccinate young in their late teens to those below 30 since the diesease is usually mild in young people.
On Sept 12, 2023 CDC itself said that "
Data from VSD and from VAERS indicate that rates of
myocarditis after COVID-19 vaccination are
highest among males in their late teens and early 20s, usually following the second dose of the vaccine."
https://www.cdc.gov/coronavirus/2019-ncov/vaccines/safety/adverse-events.html