The answers to this are:
provocative: work is already optional for holders of large capital - if it works for them, why not the rest of us?
humanitarian: everyone deserves decency (and we have enough to go around)
utopian: we are/will be rich in everything we need, so we do not need to work for basics - we will only need to work for the betterment of ourselves, our culture and civilization
practical pessimist: if we don't give the poor enough to keep them on board of the system, they will oppose it and we will have civil war
practical optimist: if we give the poor what they need to live without a fight, they can focus on working on themselves to lift themselves up - it will be a win-win situation
practical realist: taxes (and exemptions) and benefits are so complex, it would be cheaper to use UBI and probably fairer as well
I'm in the practical optimism/realism camp, although my lizard brain sometimes gets angry at some of the "the poor deserve no better, it's a fair system - they just have to work"-people and will use the provocative argument.