placement new vs assignment

/*
 * Comparing placement new against assignment.
 *
 * In the code below from main, using placement new won't
 * call the destructor of the Point(2,3) that was created in main, so
 * it's just like a std::move let's say to location pointed by pptr.
 *
 * While using the assignment will copy from a const Point& to a
 * new Point and the Point(2,3) created in main will then have its
 * destructor called (since it's a one-off created Point only for that
 * assignment expression), so you'll see an additional "destroying point"
 * output line compared to the first one.
 *
 * See[1] for a great explanation of how placement new works.
 * [1] https://stackoverflow.com/questions/35087204/how-c-placement-new-works
 *
 */

#include <cstdlib>
#include <iostream>
#include <new> // Needed for placement 'new'.
#include <string>

struct Point
{
    int x_, y_;

    Point() { std::cout << "default point constructor\n"; }
    Point(int x, int y): x_(x), y_(y) {
      std::cout << "constructor call of " << *this << '\n';
    }
    ~Point() { std::cout << "destroying point\n"; }

    friend std::ostream& operator<<(std::ostream &out, const struct Point &p) {
      out << "Point(" << p.x_ << ", " << p.y_ << ")";
      return out;
    }
};

int main() {
  Point* pptr = (Point*)malloc(sizeof(Point));

  // how is placement new different here?
  new(pptr) Point(2,3);

  // than a simple assignment
  //*pptr = Point(2,3);

  // See comment at the top of the file for difference or try it
  // yourself to inspect output.

  std::cout << "Done with constructing " << *pptr << ", will deallocate memory now.\n";
  pptr->~Point();
  free(pptr);

  return 0;
}