It's not a huge issue since you can have other datatypes to deal with strings efficiently. E.g., Haskell has Text and ByteStrings (both lazy and strict versions

It's not a huge issue since you can have other datatypes to deal with strings efficiently. E.g., Haskell has Text and ByteStrings (both lazy and strict versions) for this reason. But it is considered a design mistake that the least efficient way of handling strings was made the default.