Pietersen, of course, had his England career effectively ended in February this year.
There's also a feeling that both Pietersen and Moyes' dismissals were poorly handled—even if people believe that ultimately the right decision was reached.
Moyes' sacking was common knowledge almost a day before official confirmation arrived, pointing to a leak at Old Trafford. Pietersen, similarly, had lots of stories about his conduct on the Ashes tour slip out through the media—but few charges were more serious than whistling.
The similarities probably end there, however—Moyes appeared to be out of his depth, while Pietersen was the top scorer in the failed Ashes campaign, and appeared to have the talent, if not the backing, to continue representing England.