How does dynamic casting isolated conformances integrates with swift-evolution/proposals/NNNN-SerialExecutor-isIsolated.md at wip-isIsolated · ktoso/swift-evolution · GitHub?
When doing as? we cannot use checkIsolated(), but isIsolatingCurrentContext() could be used. But when doing as! it is even possible to use checkIsolated(). But I'm not sure if it is a good idea to have different behavior for as? vs as!.