Seems to me to probably reflect a high degree of insecurity: if you're not secure and feel the need to protect your position I can imagine some people reacting this way if Chris is telling everyone he thinks your idea is a bad one.
I've heard great teams at Apple and toxic teams - maybe more on Software than hardware (see the writeup / postmortem on Aperture which started off great but middle managers under time constraints ruined it/made it toxic).
Not sure if Apple silo-ing off teams lets this perpetuate, but then again, it's not like Google or FB have their own share of toxic groups.
You'd think something like that whole Apple university MBA program would figure out better ways of managing large numbers of people with commensurate egos, but it seems like an unsolved problem.
I don't believe the silo-ing of teams is a problem in itself. If teams are not silo-ed in a company of 150k employees, things will grind to a halt quickly.
Seems to me to probably reflect a high degree of insecurity: if you're not secure and feel the need to protect your position I can imagine some people reacting this way if Chris is telling everyone he thinks your idea is a bad one.