Whether you need masking or such level of tools is dependent on how you approach photography. You can change your method of taking photos to remove such a need for editing.
Others have responded about dynamic range and HDR, and that's one area where a particular feature set is necessary for certain kinds of photography.
Astrophotography and macrophotography both very nearly require focus-stacking abilities.
There's certainly a lot of photography you can do with just a camera, or with just a camera and very basic editing tools.
But having advanced tools opens up a whole world of possibilities. Those aren't all going to be things that everyone wants or needs to do. But there's a huge number of artists who will want or need some of them.
https://www.theguardian.com/media/2008/apr/08/reuters.pressa...
“Composition must be one of our constant preoccupations, but at the moment of shooting it can stem only from our intuition, for we are out to capture the fugitive moment, and all the interrelationships involved are on the move. In applying the Golden Rule, the only pair of compasses at the photographer's disposal is his own pair of eyes. [...]
If you start cutting or cropping a good photograph, it means death to the geometrically correct interplay of proportions. Besides, it very rarely happens that a photograph which was feebly composed can be saved by reconstruction of its composition under the darkroom's enlarger; the integrity of vision is no longer there. There is a lot of talk about camera angles; but the only valid angles in existence are the angles of the geometry of composition and not the ones fabricated by the photographer who falls flat on his stomach or performs other antics to procure his effects.” (“The Mind’s Eye” p34, 1999 Aperture ed.)
There are plenty of potential photographs that even modern sensor (or film) technology just can't do, like with questions of dynamic range. There are opportunities for cleaning up noise and sharpening to create a technically-better image. There are reasons beyond count for compositing of different kinds.
But most importantly, supporting the artist's efforts to achieve their vision is the whole point. If someone vision can't be achieved either with their physical toolset, or with their suite of tools, why should they limit themselves?
I don't think too many people manage to get a wildlife, landscape, astro, macro or night shot so well exposed that no editing is needed.