I heard about this. Please elaborate
Rakuten gives you a percentage cash back on online and in store purchases, as long as you use your amex card, and turn on the deal in your app or pc. The cashback you accumulate is tied to your profile, and can go to your PayPal acct or amex acct.
So for example, they have a $16 cashback deal for buying a year of hbo max ($100-150 ad free). If you buy that using your amex platinum, you’ll get $16 cash back through Rakuten either in the form of cash through PayPal or amex points equivalent.
Also amex is giving you $25 back on your statement if you pay for a year hbo max subscription, so it’s really $41 back when you add up both deals.
Rakuten makes using your amex plat for non travel items make more sense because you’re usually getting 1x points without it. But with it, you can get between 2.5 - 10%+ cashback depending on the deal and website