I'm really confused about not being able to change my username. Is it a safety thing?

Yes, you cannot change your username unless it breaks the CG, reveals personal information, or gives you gender dysphoria.
If your name doesn't have one of those requirements, then you cannot change it.

This is the Scratch Wiki´s statement:

No. The only way to change a username is to open an entirely new account, but please note that data such as projects, studios, followers, and forum posts will not be transferred.

It is possible, but uncommon, that the Scratch Team may make an exception upon request for usernames that reveal personal information or cause gender dysphoria, and in general this only will be done for well-established Scratchers. The Scratch Team will then transfer all projects, loves, favorites, and other information to a new account with a different username.

So, no

Removed by me

bluepig600 wrote:

You cannot change your username because of impersonation

I haven't heard that before
Where is your source

There are people who changed his username and ofcourse Gdpr

The reason you can't change your username unless you have special permission is this, to quote The Official List Of Rejected Suggestions:

8.1 Changing usernames or changing display names
If a user could change their username (or even set a certain “nickname” or “display name”), this could be very confusing for the Scratch community, especially for those following that user. In addition, this would make moderation of the website more difficult because it would be harder for the Scratch Team to keep an eye on what a user may be doing. The Scratch Team has allowed username changes only on very rare occasions, such as if the username contained inappropriate content or personal information. Generally, the Scratch Team does not change usernames on request (including for reasons such as “I do not like my current username anymore”).

You can't change your username, unless there is extreme circunstamses, like gender dyshopa (i think i spelled it wrong), personal info revealed, and if scratchers could change there username, it would be very confusing.

I do actually know someone who's username was changed, because it contained personal info, it was weird, because I though that she had made a new acount when in reality, her old one was just unbanned with a different username