Your proposal replaces my use of an array with two things, a pointer (as before) and a length. This is not too helpful, because I already could have done that if I'd wanted to.

What is missing is the ability to pass an array. Sometimes I want to toss a few megabytes on the stack. Don't stop me. I should be able to do that. The called function then has a copy of the original array that it can modify without mangling the original array in the caller.