CANDU reactors in Canada, I think are designed to be run by nobody at all.

They require heavy water to keep the reaction going. No heavy water, it just cools down.

If anything 'breaks' - no heavy water, no chain reaction.

I'm grossly oversimplifying, but you get the idea.

I suggest that if we actually put our minds to it, we could develop a kind of 'dumb reactor' that didn't require any kind of intervention at all, other than maintenance.