Around 6,000 years ago, a blast wave from a nearby supernova likely crashed into them, grinding them down and washing them away in concert with the young stars.
But we won’t be able to watch them dim and disappear until the year 3015 (give or take).
You see, the Pillars live 7,000 light-years away from Earth. The light we see from them — the light that Hubble Space Telescope scientists used to make the new image — departed from the nebula in the year 4985 B.C.E., traveled at the speed of light toward us, and arrived here 7,000 years later. We thus see the nebula as it looked 7,000 years ago.