This point is rather reductive. There are various reasons one may engage in social media and share information. An interesting story, a major event, something odd, something relevant to topics they discuss frequently; the last one doesn’t even need to involve opinion pieces. It can purely be for the dissemination of information. Sharing an unbiased Reuters report about slavery in Thailand doesn’t have to mean I’m either reinforcing my worldview nor discovering information about slavery in Thailand I didn’t know before.