Hm, I suppose so. Perhaps growing up on R-rated films has distorted my perception of what is appropriate for children
The MPAA is pretty random to be honest.
The Matrix films aren't gruesome either or have many swear words in them, they're all R.
The LOTR movies have beheadings and dismemberment. PG-13, for the kids!
All these movies were rated "suitable for all audiences" where I live.