No. That happens since you are born, you leave the comfort of the uterus, then eventually you cannot suck more your mom's tits, a new baby comes in and you are not longer the smallest one, you have to go to kindergarten,etc, etc, all those are pretty challenging/traumatic events when adjusted by age and then the changes keep coming. By all means not all changes are bad or even difficult but constantly through life you will have plenty of them. One thing I have learned in life is that you need to control very carefully your comfort and pleasure, too little and life is miserable, too much and you become indulgent, weak willed, afraid of change and you stagnate. Most humans live in the "too comfortable" spectrum (this not only means being materially comfortable, it may mean not trying to change, playing it safe, not daring to do things), so one or two whips courtesy of life could work wonders.
The word "traumatic" did not used to mean "somewhat uncomfortable". And most of the ones you mentioned are not even uncomfortable for all kids. Plenty of kids just loose interest in breastfeeding, goes to kindergarten without major issue and is curios/happy/indifferent when siblings come.
Completely agree. Life's more intense parts that make all those sweet memories that one can be proud of for rest of ones life are well outside the comfort zone.
I see it daily in some of my former peers - literally frozen in space and time. By all means if that's your goal go for it, but when these folks are confronted with somebody more active, somebody who steps out of that comfort zone when needed (or cca lives there semi permanently) their reactions tell a different story.
When I was climbing Matterhorn, (or even Mont Blanc on skis in some places) there were certain times I was shitting myself from fear of the abyss and clear and present danger all around me. When I decided to get into paragliding, first solo flights were not so much different - 1km vertical drop just below your ass is something one can't prepare oneself beforehand. Those memories, and many many more are part of my core and will be there till I die, putting a slight smile on my face whenever I remember them or see the spot from afar.
Heck, being next to my wife when giving both births was not comfortable at all, seeing all that suffering and uncertainty and being able to do very little to alleviate it, but its one of those few moments that define me as a parent and human being.