Scooter,
If I have read your question correctly you are asking why is cutting in sports seen as detrimental to a childs self esteem but being cut in something viewed as not as important is not viewed as equally detrimental..I really can't offer an objective answer...to me being cut from anything is hurtful no matter what the activity may be...as a child I tried out for color guard and was cut...destroyed my ego but I did manage to pick up the pieces and move on...excuse that was offered to me was that I was not coordinated enough...funny how things do turn around though I went on to try out for cheerleading, managed to make the team, and went on to be captain in my senior year...do I believe being cut impacted my resolve to try harder...perhaps...I was unaware of it then and can't remember now
On the flip side there was a youngman that went to HS with my son...freshman year he tried out for hockey....cut...tried out for BB...cut...tried out for Lacrosse....cut...I felt very bad for this youngman but can't even imagine how his self worth was affected...well he transferred to a HS that was in a lower division...made the hockey as well as the BB teams...even managed to have his name in the paper quite frequently
...at the elementary and middle school level I feel that all avenues of activities should be open to one and all...that is the time to be feeling the waters as to what each one is relatively good at