Earlier quoted context omitted.
Squatting is something you do to someone else's property. It implies that there is someone else out there with a more legitimate claim to the @hac handle, which there isn't. It's not as if we're talking about @google or something. If I stole your house and sold it because I didn't think you were using it properly, that would clearly be illegitimate. I don't see why the rules change when we talk about someone's twitte…
But you don't own it. X does. It's their service, they are free to apportion handles as they see fit. It is nothing like a house where you have an actual ownership claim through the deed.
It wouldn't have been so successful if everybody be called "Anonymous" meaning that they wouldn't be able to make money with it.
They've started to take this away now. Today it's some account with obviously few words. Tomorrow it might be one with wrong words. What you counted as value is nothing. It might be lost tomorrow, so why bother?