If the user’s goal was to create an object in some memory location, then new seemed like a natural approach since forwarding references, variadic templates and placement new were not a thing back in those days. As correctly pointed out by @T.C. templates were released in 1990 and placement new in 1989. Variadic templates on the other hand, became a part of C++ only in C++11.
tl;dr There was no way to forward a bunch of arguments to a constructor of an arbitrary type (as you can do these days with make functions).