안녕하세요,
다른 사용자로부터 개인 메시지를 받지 않으려는 사용자는 다음 설정을 비활성화해야 합니다:
allow_private_messages
하지만 이 옵션은 TL0에서는 사용할 수 없습니다. 이 옵션을 사용하려면 TL1이 필요합니다.
allow_private_messages_from_specific_users
도 마찬가지입니다.
그런데 왜 그런 걸까요? 완전히 새로운 사용자가 이 옵션을 사용할 수 없다는 것은 말이 되지 않습니다.
예를 들어, 여성 사용자(이름으로 여성임을 알 수 있는 경우)가 개인 메시지로 부적절한 이미지 등을 받을 수 있다는 두려움 때문에 개인 메시지 수신 기능을 비활성화하는 것이 유용할 수 있습니다.
TL0 사용자(스팸 봇이나 트롤일 수 있는)가 개인 메시지를 차단할 수 있다는 것이 더 나은 트롤링이나 스팸을 위한 '우위’가 된다고 생각하지 않습니다.
Unless you change the default setting of the personal message enabled groups TL0 users don’t have access to the PM system so the options are hidden.
If you changed that setting to allow trust_level_0 to use the PM system and the options are missing then that would seem more like a bug. 
But, as I have tested:
I have created a TL 1 user who sent a PM to a TL 0 user. This TL 0 user recieved the PM and could read it (and send answer), although he should not have access to PM system.
So currently TL 0 must have to be able to receive and read PMs although they have no access to it.
So these options should be accessible to TL 0 user no matter if they are in personal message enabled groups.
But they have an advantage of a simpler user interface. So for the first 10 minutes of reading some features are hidden.
Is sending such images to other users as a welcome message is allowed in that community? Then why do I join it, if I don’t want that? If that is not allowed, why do I need to prevent others from doing that? Then it should be the job of the moderators to handle that.
It is not allowed. Maybe some stupid idiots ignore the rules and send the PMs. The shy TL 0 user who received the PM is scared and leaves the board in panic without informing the mods/admins.
Or maybe a harmless example:
A normal male user (which behaves correct) wants to contact a female user to make a meeting in real life, but in a respectful way. In this respectful way it is allowed. (“Hello dear, are you interested in meeting me in London? Please tell me if it is OK”)
Some female users have no problems, some other don’t want that (although it is respectful). These other female users who don’t want that,
use the board just to discuss the public topics without using PMs
thats why they joined to board.
So it might be useful, that every user can decide by its own choice if he/she wants to receive PMs already at TL 0.
It is confusing not to see this options.
In my board that was the case: A new user wanted disable PMs to prevent to receive invitations to personal meetings already at TL 0 but this user had the problem not seing the options.
(In another board - not a discourse board - she had the problems that a lot of men contacted her via PM trying to meet her in real life. Then she just leaved this board in panic without informing admins. I want to prevent this problem in my board because she writes good postings and maybe other female users with the same problem, too)
This board has barefoot living as topic. In the board the topic is treated in normal way (“healthy lifestyle”), but this topic is also interesting for (stealthy) foot fetishists who are interested in meeting barefoot girls.