It's not that a number of points earned gets you status with SPG. Status is earned after a number of nights or stays in a calendar year.
Where the Amex card comes into this is that as part of your annual fee you're granted 5 nights credit towards earning Gold/Plat status.
I didn't see anything about the amount of spending on the card affecting status on the US card. On the Canadian SPG Amex you're granted Gold status after $30k spending in a year.