I've found updating my hosts file to block sites that I'd rather not visit but find myself visiting anyway and wasting time. Maybe that would help? (Honest advice, if that's what you're looking for. If I've read your comment wrong, please ignore.)

HN purposefully doesn't delete accounts to preserve the conversations and their context. There's a comment from pg around here to that effect.

Edit: here it is: https://news.ycombinator.com/item?id=6813226