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I have to disagree with this. It's really inconvenient for newer players. I remember, starting the quests, I relied heavily on the map. It maybe be a so-called "crutch", but I feel like making the map discoverable would make a lot of newbies quit quickly.
There have been a lot of times when I'm busy and doing something when some random person DMs me asking for some free stuff or bugging me to play a minigame. Maybe some sort of block system that would allow you to block DMs from players you put on the list