Mostly yes in normal conversation. The difference is subtle. "No matter how rich you are" is in the present tense, while "no matter how rich you get" is in future indefinite. For example, the statement "No matter how rich you are, you still cannot buy happiness" would be addressed to / relate to someone who is already rich while "No matter how rich you get, you still cannot buy happiness" is more of a general statement that could apply to anyone. However, the "are" can sometimes be symbolically taken to mean "get" in colloquial conversation.