If you just move or scale around whole chunks of widgets it’s okay to use AnimatedBuilder-like patterns. But there are also cases like

• Counting up a String representing money
• Drawing animated charts
• Doing Textwriter effects
• Layout effecting animations

that require dependency on the animation value.

Furthermore using AnimatedBuilder is only effective if the animated widget-tree is large. So in my opinion there is no rule of thumb, not using setState().