i personally never use queryNew to create a populated query, because it is to complicated.
i use the function query instead:
When you are asking yourself why we have 2 functions doing the same in different ways, the answer is simple.
Compatibility, we added Query with Railo 1.0 long before queryNew had this functionality, then when ACF added this functionality we had to follow.
I get your point, but i PERSONALLY see that function only as a must have and because of that not worth extending it beyond the ACF functionality. If you don't care about compatibility to ACF, use Query.