The message you were referring to was talking about code for copying strings. If you wanted an instruction to copy lots of strings, the CPU would need to know w

The message you were referring to was talking about code for copying strings. If you wanted an instruction to copy lots of strings, the CPU would need to know what a character is (which could be 7 bits, 8 bits, 16 or 32), what a string is, how it's terminated, what ascii and unicode is, be able to allow new character encoding standards etc etc. Then you would need other instructions for other high level datatypes. That's not what CPUs do, because you're limited by how much more logic/latency you can add to an architecture, how many distinct instructions you can implement with the bits available per instruction, how many addressing modes you want etc. So instead, this information/knowledge about high level data types is encapsulated by standard libraries and then the compiler below that. Most CPUs have single instructions to copy a chunk of data from somewhere to somewhere else and a nice basic way to repeat this process efficiently, and it's up to the compiler to use this.