Dismantle the Holy Trinity

[Vulcwen]

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I used the wrong word there, what I meant was "distinction". Less clear roles indeed create more variety in what a player can do on a case-by-case basis.

And yes, you could read that other thing backwards, the point is that clear roles are required if you don't want the community to mess with them. And cases you don't want that is in random groups, as you'll end up with disagreements that can result in very bad experiences. However to be able to create amazing experiences, you need to give players some agency, which is what you sacrifice when making roles clear.
Making MMOs is always balancing the possibility to have a great experience with the likelihood of a terrible experience because people abuse the system.