It looks pretty good to me , I would not do anything . Soon it will start a new ring of roots above the old ones . If mine I would wait for that to happen being careful to let the Spag. almost dry but not all the way . Then re-pot so the new roots will (end up in the mix ) any old dark soft squishy roots can be removed , by then the leaf will be almost dead and can be removed so the base of the leaf does not end up in the mix .It is a normal growth pattern , new growth from the crown , bottom leaf or 2 die off and new roots .. happy growing Gin