Disabling “View” mentions from backend?

Instead of disabling it, you’d be better off by hiding it using a bit of CSS trickery.

Try this and let me know if it works:

    add_action('admin_head', 'hide_quick_view');

function hide_quick_view() {
  echo '<style>
    span.view {display: none !important; visibility: hidden !important; opacity: 0 !important;}
  </style>';
}

This should be placed in your functions.php file.