title: speechRecognizer?.supportsOnDeviceRecognition always returns false
body: <p>I've just updated to macOS 10.15.4 and every time I check if on-device speech recognition is available I get back false. This was working on 10.15.3.</p>
  
  <pre><code>speechRecognizer?.supportsOnDeviceRecognition = true
  print("supportsOnDeviceRecognition: \(String(describing: speechRecognizer?.supportsOnDeviceRecognition))")
  </code></pre>
  
  <p>Anybody else seeing this? Are there any tricks to get this working again?</p>