Yes, it’s the same thing, basically. Being a Buddha and identifying as Brahman are equivalent, for when you are Brahman, the person is not. It’s the deepest state of non-duality, the complete realization of one’s own non-being. That’s Buddhahood.

But Gautama did mention though, that Buddhahood is eventually also to be transcended, and the person is to become an ordinary person again in full enlightenment. Brahmanic body is still a dreaming body, and Brahma itself is also illusory. Which is why even though Buddhas are technically enlightened, a fully enlightened being is called Samma Sambuddha in Buddhism. That being is you, you just have to walk the path to completion.