Neither of the proposed solutions are entirely correct (or at the very least, are misleading), since instead of keeping track of the actual finger/pointer id, they are only regarding that move event's index within the MotionEvent object, which may vary depending on the number of fingers on the screen.
For example: if the user presses the screen with one ...
You are using Mathf.Clamp to prevent it from going out of bounds. You can use it as well to restrict the speed
offset.x += Mathf.Clamp(delta.x * Sensitivity, -_MaxSpeed, _MaxSpeed) * Time.deltaTime;
_MaxSpeed is something you would need to figure out until it matches your gameplay.