What AIMSS does is never leaving you with a camera with a too slow shutter speed set manually and always at least gives you the old rule of thumb 1 / your present focal length with options to overrule ans add a suitable bias really quickly. In cases like that I don´t give my camera any thought at all - just the motif and the composition and the moment. Totally without any distractions. It has helped me a lot and many others too.
It is a reason Sonys evengelist Mark Galer has pushed AIMSS as Sony´s best “Custom Setting”. Custom because it has to be configured to one of the external buttons since it is buried in the menu swamp by default - pretty typical Sony.
With M at least I can´t lift my camera in front of any motif and just shoot without even think of camera settings. Do you really mean that you can do that with your M-mode? It turnes a Sony A7IV to type a mobile phone camera. Point and shoot if you prefer that. I see AIMSS as a type of “Insurance”. My choice between using it or not is between missing the picture and not missing it. It is not more to it than that - and I have lost many pictures during the 60+ years I have been using cameras. I know my weaknesses as a photographer by now :-).