Increased water intake is not without some benefit.
It can help deter developing urinary tract infections if you are prone to them.
Also, drinking more water can help rid your body of retained fluids (retention/bloat).
Dehydration, or even just lower water levels, activates anti-diuretic hormone (ADH), which discourages the body from excreting as much fluid, instead storing it in organs and subcutaneously.
ADH is, essentially, a defense mechanism to protect your body from losing too many fluids. Drinking more water basically deactivates ADH, convincing the body that it’s getting adequate amounts, and negating the need to “hoard” it.