Actor `assumeIsolated` erroneously crashes when using a dispatch queue as the underlying executor

Using Swift
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2

Just got to the same crash today. As far as I understand from @ktoso pitch and its subsequent proposal, this issue will be solved by implementing checkIsolated(). However that function seems to only be used by runtimes from macOS 15+. Is this right @ktoso ? Any way to use assumeIsolated(_:) in OSes lower than 15?

My current executor looks similar to @wadetregaskis with slight differences since I need to support macOS 14:

public import Dispatch

public extension DispatchQueue {
  final class Executor: SerialExecutor {
    public let queue: DispatchQueue

    public init(label: ReverseDNS, qos: DispatchQoS, autoreleaseFrequency: AutoreleaseFrequency = .inherit) {
      self.queue = DispatchQueue(label: label.rawValue, qos: qos, attributes: [], autoreleaseFrequency: autoreleaseFrequency, target: nil)
    }
  }
}

public extension DispatchQueue.Executor {
  @inlinable func enqueue(_ job: consuming ExecutorJob) {
    let unownedJob = UnownedJob(consume job)
    let unownedSerialExecutor = self.asUnownedSerialExecutor()

    #if compiler(>=6.0)
    if #available(macOS 15, *) {
      let unownedTaskExecutor = self.asUnownedTaskExecutor()
      return queue.async {
        unownedJob.runSynchronously(isolatedTo: unownedSerialExecutor, taskExecutor: unownedTaskExecutor)
      }
    }
    #else
    queue.async {
      unownedJob.runSynchronously(on: unownedSerialExecutor)
    }
    #endif
  }

  @inlinable func asUnownedSerialExecutor() -> UnownedSerialExecutor {
    UnownedSerialExecutor(ordinary: self)
  }
}

#if compiler(>=6.0)
@available(macOS 15, *)
extension DispatchQueue.Executor: TaskExecutor {
  @inlinable public func asUnownedTaskExecutor() -> UnownedTaskExecutor {
    UnownedTaskExecutor(ordinary: self)
  }

  @inlinable public func checkIsolated() {
    dispatchPrecondition(condition: .onQueue(queue))
  }
}
#endif

Is there any way to backdeploy TaskExecutors as well?