I 100% agree with what Britanica shared about water and how it impacts the scalp and hair.
Many people notice a major improvement in their hair when their water is pH friendly which is most often the case with soft water.
There is a known issue for other people who only have access to well water which sometimes can be full of lead, copper and other chemicals. When people only have access to water full of toxins and chemicals they are advised to either purchase a special water filter for their shower, or use distilled water to wet-wash their hair.
It's amazing how much difference water can make on how and it's appearance and ultimate behavior.