To reproduce:
1. Open my attached project
2. Run the scene
3. Move the game object with arrow keys
4. Observe that there are no log messages when the object drops down from a platform

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Why is it by design?

When you adjust the position, rotation, scale or parent directly you are warping the object through space which the physics system doesn't support. When you do any of these operations then you will not get the resultant "end" calls and cause other side-effects.

If you output something in "OnCollisionEnter2D" you will see it is continually entering the collision because you are effectively repositioning the object in the enter callback. You should not do this.

You are adding a force rather than setting the position directly for this very reason.

Adjusting the parent in the collision callbacks is the problem and all transform related operations should be avoided when physics objects are involved.