Microsoft is racist against minors

And won't let me download 17+(M) content because I'm 17, and not 18.
When does it change my age? I'd assume birthday, but I haven't been able to find the date in my profile on live.com.
Can I change download-able content limits via parental controls? I thought I did already....
Can I change my Windows Live ID associated with my Gamertag + keep my stuff, etc?
Can I change my Windows Live ID's 'age'? Wouldn't let me edit it when I tried...

Ageism