When the Set Digital Assistant (to MacroDroid) action runs, either manually or in a macro, it doesn't appear to work fully. In the phone Settings the Device Assistance App is correctly shown as MacroDroid, but when I tap on it, it shows that the actual Digital Assistance app is still Google, and I have to choose MacroDroid manually:
MacroDroid v5.29.13Pro on Android 12 (Samsung S21FE)
MacroDroid v5.29.13Pro on Android 12 (Samsung S21FE)