[OneDeuxTriSeiGo]

The term virtual youtuber comes from japanese for what it's worth. It's a loan word of a loan word. It's the term that is used.

And avatar is used in the space. They are "formally" called vtuber avatars or vtuber models. But the occupation/hobby is called vtubing and a person who uses them is a vtuber.

It's not that avatar isn't used. It's just not specific enough to what this is. vtubing rigs specifically aren't exactly general purpose. Some of them are and work as avatars that can be used with mocap or vrchat or whatever but a lot of them just aren't. A lot of them are "Live2D" which is a much more restricted type of model that is effectively various different transform and distortion effects on 2d images to give the perception of 3d motion.

Avatar covers a lot of things. Vtubers are a very specific subculture. They have avatars/models but to just call them avatars sells them quite a bit short of what they are specifically.