Pro is today such an overused term. Usually it just marks a higher priced product. The free trial versions of apps have their normal names and the paid (no ads, all features active) versions are called somethingsomethingPRO.
An professional that uses their machine for work might need nothing more than a decent office notebook. Webdesign, all sorts of office work, financial manager, broker, .....
3D rendering usually just needs a fast CPU and only a limited amount of actual ridiculous GPU power like a gamer does. Gaming is mostly GPU and 30% CPU at least at the higher settings. Most software people think of when workstations are concerned usually want rather more CPU than the very best possible GPU as only parts are GPU accelerated and a significant amount of work is still left to the cpu.
Movie editing needs very little GPU unless you add some effects and even there I doubt you need too much because for animation or great special effects a gpu would help save the day either. Photoshop has some accelerated filters. A few tedious things get a snappier, like you get smooth rotate. Most of the time a GPU will just sit there waiting for the user to do something demanding.
Gaming is different. It is mostly GPU and non stop. CPU only handles a little AI, networking and feeding the GPU with more data. Also gaming is heavily DirectX centric with lots of optimizations that help performance without sacrificing too much visual quality. Speed first and not too many crashes and artifacts.
Pro apps usually focus on OpenGL and pro GPUs (Quadro, FirePro) try to do their work right rather than as fast as possible with okay output. Those cards also fare better on double precision (double 64bit vs float 32bit). Logic for that is usually shut off or completely left out of geforce gamer gpus to save space or power consumption. Games don't waste time with double precision as it wouldn't offer any perceivable picture quality difference for shaders and pixels have only so much color information.
I think most actual pros of all breeds need stability. Secondly they need a fast CPU (lots of RAM) and after that there are some who benefit to some degree from a faster GPU. It is rarely the fastest GPU possible.
There ture gaming beasts with lots of power but workstations rarely even sport the best possible quadro and if, never more than one.
Gamers basically need the fastest GPU they can have with a good enough CPU. Usually the top of the line mobile CPU is a waste of money over the entry quad core and just produces heat that is better put towards a faster GPU. Gamers also don't need all that much RAM and stability isn't that big of a deal as games and graphics drivers are the weakest link anyway.