Harrasment & Malicious Intent

[Sylve]

And Squenix taking away another players name to give it to a streamer would be a PR disaster for them. Because it would be seen as favoritism.

So .. you're more OK with literal crime than perceived favouritism?

SE doesn't have to give the name to the OP, but they can sure as hell ban the character using the name, not only is impersonation a crime, it's also against ToS.
SE has every right and an obligation to intervene.

SE terminating an account for breaking ToS AND law is perfectly reasonable.
It's on the OP to try to get their name back once the offender has been dealt with.

"Square refuses to help a player whose name was taken and used to impersonate and coerce them"

"Square assisted a player whose name was maliciously taken during a transfer issue and used to coerce and impersonate them"

Which story is worse PR?
Even if the OP never gets their original name back, the one who took it needs to be punished for their behaviour.

It doesn't matter if someone is using a name as their brand. They do not own the name within the game. Names are first come, first serve.

Someone having the same name does not mean they are attempting to impersonate another person. To be impersonating, they would have to be telling others that they are the other person.

Did you even read my post?
Taken names are common, especially for streamers.
However, the difference is how that name is used.
If they just play normally, no one would even notice.
If they used the name and proclaimed they were someone they weren't, that's a crime and it has repercussions for the person being impersonated.
Public image is important to brands, even more so for streamers who can lose sponsorships and monetization if the impersonator manages to fool the right people.