Use of function_exists in future updates?

Hello.
I would like to modify some of the php files, such as removing the phrase “No comments” on posts which have no comments. Unfortunately (as far as I can tell), the php functions aren’t coded using “function_exists”, so they don’t check if I’ve already defined the function in my child theme. So I have to directly edit the php files (eg. content.php, content-single.php, comment-template.php) to make this happen, which obviously gets lost when I update the theme.

Do you have any plans to make the functions pluggable and use “function_exists” in any future updates? It would help me a lot!

Thanks,
Paul