"They are about this high." Zenyatta is 5'8" (1.72m), so he raises his hand to about how tall the townspeople are compared to him. "I would be happy to introduce them to you. While I think you might be the largest one I have met here, the townspeople come in their own various shapes. Your appearance may not invoke fear in them. Your demeanor certainly will not."

In all, he's trying to say that Skyfire should have little to fear. He has faith in the townspeople. They did not treat him with any distrust or even discomfort despite being made of metal and wholly unlike the technology available.