To be honest, the new tricks are handy time savers. I like them. But I DISLIKE the "unfit for GD" idea of this post. As some say :"It's the indian not the arrow. " PS1 is still fit for GD ( assuming you culd find a machine to run it and had the time to the effect s manually), but with a little know ledge of why things happen.. you can most of what CS5 PS can do in PS2 or 3 using maps, histogram sliders, and multiple layers and masks. Is it a royal pain... YES. as far as career does it look better on a resume to put the lates version yes ( keep in mind HR people dont know squat about design.. they are just searching for keywords given to them by managers who probably dont know squat about design either). You know .. in art /creative direction most of my work is still DEMANDED in PENCIL ( or ink).
Long answer short. NO. There is no such thing as unfit for GD unless it lack aesthetic value. It's a nice bonus or edge to know the latest toys tho, if you can get your hands on them.