Buttons as "3D Blueprint" or Widget ??

Hey Gu.ys/rls o/

Is there a reason to keep buttons as widgets with flip book animations in menus, and not as a “3d clickable blueprints” with animations particles and stuff straight in scene ?
The one big thing that comes to my mind is anchoring, but the rest seems to be easier to make as a scene blueprint.

Main Menu, Hub Menu is also a 3D scene with objects that corresponds to play, continue, exit that play some animations on hover etc.

Best regards