I, too, think that the poll asks the wrong question. Taken in isolation, the answer must surely be “yes”; modern techniques are invaluable in photo restoration, but it is the extent to which they are used which gives me a problem.
I have used modern techniques myself e.g. to stitch together a photograph which was ripped in half many years ago and to make viewable badly faded, poorly exposed, damaged or mis-coloured images, but things such as colourisation and trying to make grandma look like she was photographed yesterday is, in my mind a step too far.
Old photographs have their character and, when restoring, it is essential to know when to stop.