In the site logs (Drupal 9.5) I see:
Warning: Drupal\coyote_img_desc\Hook\NodeViewAlterPostRenderHook::hook(): Argument #2 ($output) must be passed by reference, value given in Drupal\Core\Render\Renderer->doTrustedCallback() (line 101 of /opt/drupal/web/core/lib/Drupal/Core/Security/DoTrustedCallbackTrait.php)
edit likely a mistake on my part.
In the site logs (Drupal 9.5) I see:
Warning: Drupal\coyote_img_desc\Hook\NodeViewAlterPostRenderHook::hook(): Argument #2 ($output) must be passed by reference, value given in Drupal\Core\Render\Renderer->doTrustedCallback() (line 101 of /opt/drupal/web/core/lib/Drupal/Core/Security/DoTrustedCallbackTrait.php)