Are excessively long display names for political messaging allowed on SE sites?

For people supporting a fellow user and highly-respected mod, it is but a small token of solidarity; it creates unity and fosters a strong sense of community.

You are the first I have heard mumbling irritation at these long usernames. However, some extremely long usernames are not mildly political in nature: there is more than one user who regularly changes the string of words connected to their core identity, and they have been around for years. And as someone else said in the comments, you only need to write the first three letters (I'd play it safe and go for five) and a notification will be received.

From the link supplied by @Rubiksmoose in the comments:

If the first word in the display name is at least three characters long, then there must be a starts-with, case-insensitive match of at least three characters in the display name. This means @a and @ab will never match anyone, unless a user uses a first word that is only two characters. Like: @Jo will notify Jo Miller, but not John, and @B. will notify B. Gates, but not B.Gates. If there are more than three characters in @name, then all given characters must match (neither @alix nor @aliceinwonderland will match user Alice).

I am certain Stack Overflow is not run amok by usernames containing "Support blah, blah" or "Reinstate blah, blah". In fact, the actual number of usernames containing the name Monica on MSE is quite small; it was estimated to be around 154 on November 8.

All things considered, it's a very small annoyance in the grand scheme of things, don't you think?

There is precedent - at least, on Politics.SE - for removing inappropriate political statements from usernames. Specifically, someone appended "Is RBG Dead Yet?" to their username, in reference to Ruth Bader Ginsberg, and a moderator decided this was inappropriate and removed it. I imagine your examples of "Abolish ICE" and "Punch Nazis" may well be considered inappropriate too.

Statements about reinstating Monica, however, don't strike me as being political. The main objection the community has to her dismissal is that it was done without warning, without evidence, and without any chance for her to respond as she was observing a religious holiday at the time. Those are not politically-motivated objections, and so "Reinstate Monica" should not be considered political messaging.

I'm also aware that the community as a whole is currently quite... tetchy about the idea of SE censoring them, especially with regards to Monica and her situation. If, tomorrow morning, SE took action and removed the pro-Monica statements from everyone's usernames, there would be outrage. I suspect SE know this and, regardless of anything else, are letting it slide because to do otherwise would make things even worse for them.

Yes. They're allowed so much as they've not been removed.

Now, arguing for punching someone in the face isn't quite the same, but sure, try it. I doubt anyone supports not punching Nazis in the face, do they?

I hadn't considered it before, but I think it's important to think about the relevance of the message. While I agree with the idea of ridding the world of Nazis, it's not something I'm going to stick in my name, as it is of little relevance on this site (or any site on SE at all).

As you've changed your question:

There's no policy other than not being offensive. If you change your name to something offensive, then a mod will likely revert the change, with the possibility of a suspension or further action depending how insulting the name was.

Who decides what's allowed? That's down to a combination of the mods and community managers. Right now, you can infer that the support for Monica via usernames, is allowed - because it's not being removed.

I personally think of it this way - those posts which portray little useful information to me, are the ones I spend the least time thinking about. If someone posts an insightful or helpful message, the very least I can do is read their username.

To me, the purpose isn't for those in Meta.SE already, but for the content sites. (Granted, my participation in those has been greatly reduced since this.)

However, I do see in other metas, people asking "what's all this Monica stuff in the user names?" That allows the curious to be redirected to the "Firing/Cooperating" post or other relevant ones.

In other words, it keeps "the Monica thing" from being merely a "meme of meta" but a reminder of something that affects MANY of the SE sites in MANY ways, and it's an invitation for others to learn about what the SE organization has done and could do again.

To me this is all kind of unsolicited advertisement, like spam. I don't think the purpose of user names should be to convey messages of any kind, it could be seen as abuse of the name feature (depending on the outcome of another discussion about what user names are actually good for).

I really support Monica and I think the company treated her really badly, but I don't want to be reminded on a daily basis of who else of the more than 1500 people who support her is doing so too. The gofundme campaign "Defend Monica from Defamation by Stack Overflow" has collected so much money from more than 370 donors already, that naturally at some point everyone who wanted to support her this way will have it done already. Is there a point in advertising for her anymore? I'm not sure that talking about her case is helping her more now. The matter is in the courts and must be resolved there. It cannot be resolved here.

(Mis)using the name feature distracts from the content. It's very similar to adding your favorite statement at the end of every contribution. I think it weakens the value of the content and that's the thing I don't like about it. I could probably solve the problem with a userscript (shortening user names) for me though.

I support Monica, but because of it, I don't need to be convinced. Instead, I'm a bit bored by these messaged names. But in the end it's the company decision. They could maybe invent a FAQ on name usage.

I argue that they are already forbidden by the rules.

From the help center:

Do not use signature, taglines, greetings, thanks, or other chitchat.

Every post you make is already “signed” with your standard user card, which links directly back to your user page. Your user page belongs to you, so fill it with information about your interests, links to stuff you’ve worked on, or whatever else you like!

Thanks and other statements of appreciation are unnecessary, and, like other chitchat, should not be included.

If you use signatures, taglines, greetings, thanks, or other chitchat, they will be removed to reduce noise in the questions and answers.

Everything outside the user page, including the display name, should not contain taglines, signatures, or other chitchat that is irrelevant to the topic being discussed. Chitchat can be removed.