Retry logic introduces too much cognitive complexity

Spin off from https://github.com/TraceMachina/turbo-cache/pull/324 and I've noticed this in other parts of the codebase as well. The current way to add retry capabilities is this:

self.retrier
    .retry(
        retry_config,
        unfold(thing, move |thing| async move {
            // Do something.
        }),
    )
    .await

That's three levels of nesting where the // Do something can get fairly complex as it basically contains the entire stream/state handling logic. Surely there is a more readable way to do this.