The previous owner should have let Landry go way before JJ bought the team. Instead, he could not do it. In comes JJ and poof...Landry is gone.
It looks bad on JJ because the perception is "Who is this random guy and what right does he have to come in and fire a legend?"
I believe the fan base would have accepted the firing had it been anyone but a stranger to do it. I think there has been resentment at JJ since that day. I don't think fans liked JJ too much even after the third title.
Make no mistake though, Landry had to go. It was time.