Pretty normal stuff. I think given the nature of being pants-ed, the response is appropriate. I know in this case both were 6 year old boys, but every child should know that forced nudity is not ok. Pulling down someone else's pants (or your own) crosses over into a serious offence pretty quickly. It shouldn't be trivialized at any age. Physically protecting yourself should be permitted & encouraged.
All three of my kids had protecting themselves incidents fairly young. As a toddler my youngest daughter was removed from a pre-school for biting. The other kid had bitten her before (broke the skin), and was given a second chance. She retaliated when he struck again, and they were both expelled. In this case, she was too young to really talk things out with her, but I made sure she was not discouraged from defending herself. Get away and tell a teacher if you can, but don't take physical abuse.
My oldest daughter was in maybe 2nd grade when a boy hit one of her friends, she threw him down and kicked him. A little different situation. She was told that while it is good to stand up for yourself and your friends, maybe kicking him when he was down was a bit much (even though I secretly approved).
My son maybe doesn't fit the mold of self-defense 100%. He had an ongoing feud with this other boy from like 6th grade to 8th grade. He ended up in a fist fight in the boys room at lunch. It was a scheduled event with a large audience & video being posted on YT. Rightfully suspended and 100% discouraged at home.. We took all his electronics for a month. But I wasn't terribly upset because it is part of growing up.
