Warren and Sanders' social programs are 100% possible. But their promise to fund it all by soaking corporations and the ultra-wealthy isn't. Countries that have programs like theirs have to tax the middle class to do it.
But none of that will fund Medicare for All.
I think many of Warren's ideas for reform, like codetermination and regulations on private equity, are good. Others, like her wealth tax, I don't think are fleshed out.