No, it's different. For instance, gift-giving is a really big deal in Asian cultures. It's not about throwing lots of money around, it's just showing that you're thinking of someone, so gifts can be very small and inexpensive. So gift-giving is certainly a valid love language, just like physical touch, words of affection, etc. Some people just really like to give their loved one small gifts, and some people really like getting them. They can be small clothing items, candies/food, whatever.

Diamonds aren't "small gifts"; they're absurdly expensive ornaments. Their primary purpose is so American women can show off to other women how much money their husbands have. It's a bit like having a really expensive luxury car: it's a signal to others to show you're rich, not a way for someone to show affection to another.

Edit: About Asian cultures, I'll also add, it's just just lovers. Coworkers will frequently get each other small gifts, or gifts for everyone on the team. This is usually small food items, not anything at all expensive. They might do this if they travel somewhere. I had an Asian (i.e., he had just moved from SE Asia for this job) coworker once give everyone on our team some nice variety of tea, for instance.