Take a look at https://support.na.square-enix.com/faqarticle.php?id=5382&la=1&kid=68216
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■Harassment
“Harassment” means speech and/or behaviour that inflicts deep emotional distress on another person. It is an extremely serious violation. Where Square Enix determines that harassment has occurred, a penalty equal to or higher than “Temporary Service Account Suspension” may be imposed.
Below is a non-exhaustive list of behaviour that could constitute harassment in Final Fantasy XIV:
・Discriminatory expressions based on race/nationality/thinking/gender/sexual orientation/gender identity
・Discriminatory expressions about a state/religion/occupation/organisation, etc.
・Obscene/indecent expressions
・Actions that inflict emotional distress using content related to historical events or crimes
・Stalking
・Disclosing or indicating personal information such as contact details with the aim of meeting up in the real world
・Disclosing or indicating another person’s real world personal information without permission
・Other actions that are generally regarded as actions that inflict deep emotional distress on another person
These are prohibited in all places where expressions can be made, including chat (including Quick Chat and Emote), markers, comments and names. With regard to character names, if a phrase equating to harassment is formed within the full name, this is also regarded as harassment. In the case of a group action, all of the members involved will be subject to penalties.
There may be other types of harassment that do not fit into any of the categories described above. Square Enix may determine that conduct constitutes harassment, even if such conduct is not expressly prohibited herein.
■Nuisance behaviour
“Nuisance behaviour” means speech or behaviour that hurts others or obstructs game play, but which is not classified as harassment. Even if it was not the intention, a penalty may be imposed if the end result was that another person was hurt or obstructed.
Below is a non-exhaustive list of examples of nuisance behaviour:
◆Offensive expression
“Offensive expression” means an expression in general that inflicts emotional distress by being offensive to another person. Offensive expression may include:
・Aggressive expressions such as violent language/slander/insult/threat.
・Expressions that provoke or belittle another person, such as excessive criticism, negation/ridicule
・Expressions that significantly lack consideration for another person
・Expressions that unilaterally reject another person’s opinion
・Expressions that any reasonable person would find offensive
・Expressions that compel a playing style
・Expressions that attempt to unilaterally exclude someone from the game or content/community, etc.
(Except when in accordance with rules set by an administrator such as a Free Company Master)
・Expressions that contravene public order and morals
・Other expressions that are offensive to another person
Offensive expressions are prohibited in all places where expressions can be made in Final Fantasy XIV, including chat (including Quick Chat and Emote), markers, comments and names. Use of an offensive expression in the form of a character name is also regarded as nuisance behaviour.
It breaks TOS because it falls under “nuisance behavior.” They’ve stated in the past that they’re aware of DPS parsers, and they’re willing to look the other way on them, as long as you’re not using them to criticize random strangers.