No, you're right to ask that. It's an interesting question to me in this era of time and regarding the merits of stoicism in general. One of the most highly regarded stoics (though he never explicitly identified as one) was the father of a horrible megalomaniac.
I don't think it'll be possible to ever know why that happened and how, but it's worth being suspicious of.
One of the main issues with stoicism (from my perspective) is that people can easily think they're engaged in the philosophy internally, yet they'll rarely if ever practice it externally in the world. It's easy to think Aurelius was practicing it externally because of how he expresses himself in text, and how his time as emperor was positively renowned... But this doesn't necessarily mean he was engaged in practicing the philosophy holistically in all aspects of his life. Maybe he was a bad father. There is evidence that Commodus didn't receive as much guidance as Marcus himself did, which is odd. Marcus was ill and facing the worst kinds of things, yet you'd think he'd have the resources and sense to ensure his son was receiving training and guidance to greatest extent possible. It's easy to be critical, though. He faced tremendous losses and stress in his life that would likely wear me into a pulp.
But then there's also the possibility that the winners write history, and those who assassinated Commodus ensured that records of his rule were made to seem horrible. It's hard to be certain of what really occurred.
Still, there are likely more stoics out there who try to think like a stoic but don't act like one. It's the same with any philosophy. Bringing it into practice is the hard part, and most of us fail to some degree or another. I do think stoicism is particularly vulnerable to this mistake though, but that's only based on intuition and anecdotal experience.
I don't think it'll be possible to ever know why that happened and how, but it's worth being suspicious of.
One of the main issues with stoicism (from my perspective) is that people can easily think they're engaged in the philosophy internally, yet they'll rarely if ever practice it externally in the world. It's easy to think Aurelius was practicing it externally because of how he expresses himself in text, and how his time as emperor was positively renowned... But this doesn't necessarily mean he was engaged in practicing the philosophy holistically in all aspects of his life. Maybe he was a bad father. There is evidence that Commodus didn't receive as much guidance as Marcus himself did, which is odd. Marcus was ill and facing the worst kinds of things, yet you'd think he'd have the resources and sense to ensure his son was receiving training and guidance to greatest extent possible. It's easy to be critical, though. He faced tremendous losses and stress in his life that would likely wear me into a pulp.
But then there's also the possibility that the winners write history, and those who assassinated Commodus ensured that records of his rule were made to seem horrible. It's hard to be certain of what really occurred.
Still, there are likely more stoics out there who try to think like a stoic but don't act like one. It's the same with any philosophy. Bringing it into practice is the hard part, and most of us fail to some degree or another. I do think stoicism is particularly vulnerable to this mistake though, but that's only based on intuition and anecdotal experience.