Plans include:

- Conversion into an interstellar multigenerational ark.

- The end piece for the Martian Space Elevator, where spaceships
will dock at and depart from for destinations around the Sol system.

- Completely mined for materials to make the Dyson Shell.

- Completely converted into nanotech spaceships and/or an Artilect.

- Used as a weapon in the upcoming Martian Colonies war with
Earth for independence.

- Used as a weapon to stop relativistic spaceships being hurled at
us from an ETI competing for galactic resources.

- Future explorers discover that I. S. Shklovskii was right about
Phobos being a giant repository of artifacts and knowledge from
the ancient Martian race that once occupied the Red Planet
before everything dried up and the canals didn't pan out.

- Future explorers discover that Carl Sagan was more right than
he ever knew when he described Phobos as a "diseased potato"
after seeing the first closeup images of the Martian moon from
Mariner 9 in 1972.

They then learn what kind of creature likes to eat potatoes
that are 22 miles across.

One thing is true, unless humanity goes extinct or no one else
ever visits the Sol system in the next 11 to 50 million years,
Phobos, Deimos, and who knows what else in the Sol system
will likely not remain as they are now.