Is it possible to avoid processing a headshot or portrait of an individual using a digital processing software like Adobe and Topaz?

Oh definitely! It is possible. I personally like sticking to what I consider reality in any photo I take especially when it comes to family, friends or co-workers. Well when I say co-workers I mean people I network with in the field.

With these photos I want to know that when I pull out my stock of images in 20 years time, they will be true to like to jog my memory of time past.

Mind you digital cameras do process your images when it is taken. Each camera has a sensor and on that sensor are little holes that capture the photons of light that falls on it. The light is converted to pixels. The pixels are used by the camera or your smartphone to generate an image of what it thinks you might look like. The software used to create the image of you will differ from camera to camera.

I then use the file generated to "fix" the camera's shortcomings. Hence the reason I have to process the image after it is captured.

In reality photography is complex and it is for this reason you will prices will differ from photographer to photographer. The closer you stick to "reality" the cheaper it will be. Poor lighting plus no processing equals lower price. Reality is complex. Decades ago photographers process films using chemicals. The image captured using a lens of choice and how the shot was framed could be manipulated in the darkroom. All this processing, is it truth? Is it reality?