and just letting it to do whatever it thinks it should do, without a human intervening, is a good plan?

Depending on the breadth (and value) of the sandbox: Sure? Why not?

To extend what may seem like a [prima facie] insane, stupid, or foolhardy idea: Why not send the output of /dev/urandom into /bin/bash? Or even /proc/mem? It probably won't do anything particularly interesting. It will probably just break things and burn power.

And so? It's just a computer; its scope is limited.

Discovering that is the entire intent of this experiment, yes.

the "best practice" suggestion would be to do this in a sandboxed container