That's a valid argument against ever performing any dig whatsoever, since it's always true that future archeologists might have better technology to extract more information from anything you find.
Most regions have databases full of known sites that are unexcavated because there's never been a justification for digging.
So in programmer terms, most potential sites never make it out of the priority queue
Radar, X-ray, that sort of thing
And "geophysics" were used to decide what and where to dig in most of them. They're making new episodes now, as well.