[dantillberg]

I'd say it's fair to call this a footgun, though not a bug. The context is really only intended to apply to the goroutines. And Wait has to cancel the context to prevent a resource leak.

I suggest in general using function scoping to drive the lifetime of contexts, etc. This works also for defers and tracing spans in addition to the canonically shadowed `ctx` variable.

There is an old issue in the tracker proposing changes to alleviate this: https://github.com/golang/go/issues/34510. The original author (bcmills) of the errgroup package shared insight into the design choices/tradeoffs he made.