Seriously! I know it happens but I feel like it's rare to see someone seem to explicitly argue that someone's business success should be a mitigating factor when considering their crimes.
While not to this degree “mitigating circumstances” is a concept in law, so while I disagree with OP, it is a thing of sorts in some traditions of law.
That's not what mitigating circumstances are for AFAIK.
Here are the examples given in a law dictionary :
"a young man shoots his father after years of being beaten, belittled, sworn at and treated without love. "Heat of passion" or "diminished capacity" are forms of such mitigating circumstances"
mitigating circumstances are conditions that explain and partially excuse a behavior. If anything, being a very wealthy exec that does not need money but still stealing would be an aggravating circumstance.
However, if you look at prison terms, whether this person is a danger to society or not is a big factor. We could also talk a lot about imprisonment and whether it should be used as a punition or only as a way to protect society against some very limited cases of dangerous individuals.
This should have absolutely no bearing on how the justice system handles him.