Moved into an older home and found plastic sheeting was applied to cinder blocks in basement
The plastic will reduce the moisture, bare cinder block walls are almost always damp, there may be a drain tile at the base of the wall to take the moisture away, I would leave the plastic in place. I have rarely found dry cinder block basements so this will be something to watch. A dehumidifier will help dry things out and prevent mold growth. Making sure the gutters drain away from the home and the ground graded so any water drains away from the home will help to reduce chances of moisture making its way through the walls.