The person is inseparable from the root cause.
Then "root cause" means basically nothing
I hope you don't work in technology. If you do, I hope I never work with you.
Blameless post-mortems are critical for fixing errors that allowed incident to happen.
In that case let's just shut down the FAA and any accident investigations.
It's not processes that can be fixed, it's just humans being stupid.
I'm guessing you believe that a person is always completely responsible for their actions. If you are doing root cause analysis you will get nowhere with that attitude.