> Casing is usually not meaningful even in written language. "Hi, how are you?" means the same thing as "hi, how are you?" Uppercase changes meaning only when distinguishing between proper and common nouns, which is rarely a concern we have with file names anyway.

The number of spaces is usually not meaningful in written language. "Hi, how are you?" means the same thing as "Hi, how are you ?". I don't think it's a good reason to make file system ignore space characters.