Indeed, this is a relatively trivial problem. There are reasons you might want to do something like this (like if you are trying to parallelize your sim) but I'

Indeed, this is a relatively trivial problem. There are reasons you might want to do something like this (like if you are trying to parallelize your sim) but I'd slot that under "open research problem that nobody agrees on". There are a lot of problems with global state in games, but entity values are not one of them, mostly. Problems do crop up but you just deal when they do.