It took 21 posts for someone to mention equal rights.
Luckily, Sexobon has already answered that. Gun ownership wouldn't be a
right (anymore), just a widely held privilege. Nothing about equal
privileges. No issue.
Dang, that was easy. Next!
Half-seriously, young males pay more for car insurance because they're more likely to have expensive crashes. If you can make it harder for them to get insurance, why can't you make it harder for them to get guns?