it’s enough to pass “profileNameSetting.value” to the computedFrom. you don’t need to specify “profileNameSetting”.
but you do need to acount for null inside your getter.
return this.profileNameSetting.value; will throw when this.profileNameSetting is null or undefined.
simply change your code to
@computedFrom("profileNameSetting.value")
get profileName(){
return this.profileNameSetting && this.profileNameSetting.value;
}