Catch-22: since future archaeologists have better technology, no digs are performed right now—thus archaeological technology is not needed, and there is no pressure to improve it.
They had radar and geomagnetic mapping back in the 1990s, at least - Time team did ~250 digs that were broadcast on channel 4 and are now all on youtube, most in HD now.
And "geophysics" were used to decide what and where to dig in most of them. They're making new episodes now, as well.
