Our brains trick us to breath on defaults adjusted to our surroundings.
What I have found working to slow down breath is:
1st willful exercise repetition,
2nd changing surrounding environment and lifestyle (nature, decluttwring, idleness, peaceful eating, proper sleep)
3rd gaining awareness about trigger mechanisms (overcommitments, overexpectations)
It is all self-regulating. And pretty much what mindfulnes, meditation, prayer or forest walk brings.
People don’t like anxious people so it is part of charisma development like you do training for spiritual leadership or relational healing. Less anxiety means more tolerance for risk, ambiguity, etc. it is not “put it all on 7“
Additionally, there's a practice called "walking meditation" [0] that can also be useful to practice this area of skills.
I always thought that was part of their weirdness and maybe even some personality trait that led them to this sort of thing, but knowing it's an active choice makes it even weirder somehow.
Remember to blink!
Common physical reflexes, autonomous responses, and subconscious regulation, are there as aids to us. The fact that they are not universally beneficial is one of the purposes of having higher level control. Not to universally suppress responses, but to notice and cope when they misfire.
It would be interesting to have a map of breathing patterns across a wide variety of situations, to identify the range of situations where prolonged exhalation is adaptive.
My guess, based on the common reflexes of mouth clamping and breath holding before great physical exertion, is that prolonged exhalation is part of an adaptive psychological orchestrator for when we prepare to take on something difficult, risky (but necessary), or that needs a fast strong response.
Our fast acting emotions, and slower acting moods, are similar guides. Patterns of stimulus and response from our baseline physiology and psychological, that we absorb into our higher level operation, as generalized guides for analogous responses to contexts at higher abstraction levels.
With minor maladaptive responses inevitable, if we don't pay attention. And severe maladaptive responses often ingrained as overcompensation for situational or developmental traumas.