Think of a piece of string over your shoulder joining your right and left hand, when one moves forward the other moves back.
The question then is which one do you move first to initiate the change. Either will effect speed and rate of descent.
The concept of point and power is that you start the approach from the correct position, typically 500ft at 1 mile. If you hold a constant aspect (elevation) to the runway, the aircraft will maintain an approach path that is a line of constant elevation. If you maintain a line of constant elevation there is now only one variable, airspeed, which can be corrected with the throttle. But remember if you move one you have to move the other albeit slightly.
If you use pitch to control airspeed, it is often coarser resulting in a constantly changing aspect, which results in constant changes of power to correct the height profle. The RAF preferred the Point and Power method for flying scholarships as it prevented students going low on the approach.
If you fly the perfect approach, nobody will know which method you are using. In my experience, point and power results in a smoother approach arriving at the correct point on the runway, but not everybody would agree.
You use elevator to maintain level, you use it to maintain height in a turn, so why not use it to maintain the descent profile in a powered approach. If you have no power or insufficient power that is another matter.