Do you understand that this just blocks accounts from doing certain "spam tasks" until the account has spent FIVE FUCKING DOLLARS? Five is not a lot of dollars. It's not five dollars a week, a month, or a year. It's over the life of the account.
Because Steam accounts can be made in an automated fashion, this will greatly ramp up the effort needed by spammers- they'll have to steal cards or spend money.
This is to shut down spammers. Do you seriously mean to tell me you've been using Steam and have never spent five dollars, ever?
I used Steam for 5 years before spending a single dollar on steam.
How, I bought games at a store (be it online or physical).
That being said, I never participated in anything Steam offered and realistically still dont (it's just something that updates itself and every now and then refuses to work until I reboot). Also I completely understand why Valve is doing such a thing.