A lot of times I see people focusing on their static posture, which is just your standing posture without movement, by actively engaging muscles consciously. It sounds nice until you have to think about something else, almost immediately.
Ideally, we would be able to stand with good posture without having to consciously exert ourselves however long we want. We should be able to be in any natural position statically and feel fine. A good static posture comes from a great dynamic posture.
To have a good dynamic posture means that while going through natural movements, we should throughout the range of motions, have the right posture that our body in that place and time needs to deal with the impact and disperse it throughout the entire body. Having properly tensioned and balanced fascia following the principles of tensegrity, and the myofascial slings system, we can stay in a static posture for longer periods without experiencing discomfort.
Following and prioritizing the big four, standing, walking, running, and throwing in my training has been the only thing to help my posture without putting any mental effort towards it.
Focusing on static posture is most likely not enough trauma being induced into the body to make effective changes that override the nervous system and muscular patterns in movement. There needs to be a greater degree of trauma closer to our biological locomotive blueprint than the passive trauma happening every second you’re alive.