Security Writer 
Valve: “We need a credit card on file to prove you’re 18”
Me: “My account is 23 years old”
Valve: “That just proves your account is old”
Me: “A credit card just proves you know someone with a credit card”
Ok this is interesting.
The desktop app has no such restrictions, only mobile.
yetzt@SecurityWriter using a desktop is dating yourself. as an old fart.
Kye.br 
@yetzt @SecurityWriter But, it’s steam. How can you play games without a desktop.
Wilfried KlaebeSteam Deck?