Pascal strings have the issue that you need to agree on an int size to cross an ABI boundary, unless you want to limit all strings to 255 characters and what the prefix means is ambiguous if you have variable length characters (e.g. Unicode). These were severe enough that Pascal derivatives all added null terminated strings.

Took a bit for languages to develop the distinction between string length in characters and bytes that allows us to make it work today. In that time C derivatives took over the world.