10 million is too long a time frame on human scale, given that humanity looks so drastically different even compared to 50k years back, and agriculture is also some 14k years old. If humans manage to survive on mars for 10 million years, they would be advanced enough to be out of it.

Don't fear Phobos.

It's small enough that we'll be able to move it (if we haven't mined it apart by then).