What’s actually being punished? Would she have been sentenced to 8.5 years in prison if she pushed an 87 year old who was slightly less frail and instead of dying sustained major injuries? Would she have been sentenced if she pushed an extraordinarily healthy 87 year old who knew how to gracefully fall and sustained no serious injuries?
It seems that the act of pushing alone isn’t enough to sentence a person to nearly a decade in prison. There was likely no intention to kill, though that was the outcome. What if she sneezed on the 87 year old, and in a fit of panic the 87 year old fell over and died? Again, no intention to kill, though that would still be the outcome.
I think it’s clear this should be punished more intensely than sneezing, pushing an old person would very commonly result in serious injury, so this is definitely assault.