I will copy the content of my WoW Classic General Discussion post:
A Hardcore PvP server gives WoW Classic one more game mode, which has another focus, very attractive for a certain profile of players that is not limited to WoW. It brings it closer to being a sandbox, because you can do things, with risks and strong consequences. It’s not to play WoW in the same way. It would give timelessness to the server, it is always a good time to start and play some role in the attempt to dominate (or survive) the server, either for your faction or guild, opportunity to gain some fame in the server, because the players who reach 60 and last longer will surely be known, and when someone falls, will be remembered; there will be times of dominance of some and then of others. Obviously there will be ganking attempts, so the social part will be more important than ever, considering that the best way to level will be in a group. Level your character to be a true soldier of your faction, and truly live the war between the Horde and the Alliance. As Achilles said, the gods envy the mortals, because when you can die is when you feel more alive.