I, for one, would gladly trade threaded GC and unchecked effects for checked exceptions...
Unless there is a way to implement some kind of poor man checked exceptions with unchecked effects?
Please see [1]. Around 28:45 the talk moves to effect types. At around 29:25 the proposed mechanism (with throw) is literally described as "checked exceptions".
AFAIK, this is all part of the roadmap.
[1] https://www.janestreet.com/tech-talks/effective-programming/