[irrational]

Professional animators are artists. They need professional animation tools, like flash, to work with, not svg/webgl/unity that a programmer would be more comfortable with. They need things like a timeline, character library, animation pallet, built in tweening tools, etc.

[dosshell]

Ah, I understand. thanks for the clarification :)

(Unity do have animations tools for artists (it is partly made for artists) but not so good for vector graphics and not close to flash, and definitely not back then.)