Is wudu largely symbolic?

There's some aspects of wudu which seem to indicate it's not literally about purity. E.g. 1. Passing wind is somehow countered by wetting/washing one's face, arms, and feet, and nothing is done about one's bottom area. 2. Urine inside one's body is fine. However, passing that same urine breaks wudu, yet cleaning one's genitals does not renew wudu. 3. It's good to make wudu before sleeping, despite sleeping breaking wudu. 4. The actions performed are specific, and not just "clean those areas". This motivates my question: **Question**: Is wudu largely symbolic? Maybe it cleans the body to a certain extent, but it wouldn't be considered up to par with today's hand washing standards, given our understanding of microorganisms.