One of the rules about playing Final Fantasy XIV is that players are to a limited extent liable for what they do and say outside of the game while still being linked to the game itself. Case in point: The streamer Arthars was suspended from the game on a stream due to harassing another player due to damage numbers. Damage meters are not present in the game itself, but applications for parsing damage are well-known in the community.
For those of you unfamiliar with the rules of the game, the ToS agreement for FFXIV clearly spells out that third-party software such as the aforementioned damage parsing tools is prohibited and is grounds for having your account suspended or terminated. Despite these rules, Square-Enix has historically taken a very laissez-faire approach to third-party tools in connection with its games, with the majority of progression teams using these tools and sites compiling data from these parsers in public view.
As such, many players see the situation as something of a gentlemanly agreement wherein players agree not to misuse the tools (for example, harassing someone in a random group) and the GMs tacitly do not hunt down people using them. It remains a violation of the rules, however, and players on Reddit have already argued that this is a fine example of the studio making sure to discourage harassment and brigading by fans of streamers. (It’s worth noting that Blizzard has been stepping up its examination of out-of-game toxicity as well.)
There is, of course, a great deal of ongoing debate about how much studios should do to combat toxic behavior within games and outside of the game proper, but it’s clear that Square-Enix has established a pretty firm line here. “Running a damage parser while streaming and harassing another party member” is asking for a suspension.