Draymond is the most underrated player on the Warriors since all the attention goes to Durant, Curry, and Thompson. Guy is a spectacular all around player and does every little thing to help his team win even though it doesn't all show up on the stat sheet.
How can you say that he is underrated? He is already a starting line up of a super team, that already means a lot. And the coach trusts him so much that he is being put in charge to guard star players of the opposing team. Bandwagons may only see the top stars but I am sure real sports fans recognize his talent and dedication.
Draymond can be the front line of GSW. His been the big guy since then that is why he was very confident of telling Durant that they've already done it before and they will still can even if his not on their side. Draymond obviously as you said is not under rated because he is on the starting roster line up and that only means that the management values him a lot.
It is obviously exactly he fans who actually don't understand what a basketball sport is lol.