Could Oracle consider creating a OOTB function that would let us assign an object type's attribute — within the SELECT clause of a query?
modify_object_attribute(object, attribute_name, new_val) returns object
modify_object_attribute(my_sdo_geom, sdo_gtype, 3306) returns sdo_geometry
More info here: Modify object attribute/property — without creating custom function
Yes, it's possible to do that kind of thing in a custom function or an inline function. But there are cases where we don't want to create a custom function or an inline function. An OOTB Oracle function would be simpler/preferred.
(I'm far from an expert. So I might have misunderstood something.)