I honestly think it's https://godotengine.org/features/, though I do think the GUI-only WYSIWYG creation flow hits a brick wall a little earlier than Flash did. Lots of content being made with it though!
If you're being honest with yourself, not even close. Maybe if you Frankenstein Blender for asset creation and Godot/Unity for scripting, but it would be just as much of a monster as Shelley's.
https://docs.godotengine.org/en/stable/tutorials/animation/i...