In addition to the things you mentioned, there’s also the lack of a “walk away” factor.
A person pretending to be a cop conducting traffic stops has the option of stopping at any time, getting back in his car, and driving away if he starts to lose control of the situation. A person pretending to be a prison guard can’t do this.
And per the New York Times, Trump indicated that his primary motivation for doing this was because he was a Republican who was “100 percent for Trump.”
For stealing the identities of a dozen people and absconding with hundreds of thousands of dollars?
If I had to guess, probably for breaking the rules.
Actually, it was reportedly because he was in protective custody due to death threats, but that is according to Santos himself (a known liar), and repeated by Trump (ditto).
Also, press reports say that Santos was, in Brazil, a supporter of Jair Bolsonaro, who Trump would almost certainly regard as politically adjacent to himself. I have no reason to think Sandos hasn’t voted for the Trumpy right whenever he could.
So the victims of Santos’s crimes will apparently no longer be entitled to restitution. IANAL, but I assume that they could sue in civil court. But I’m guessing they won’t: Santos doesn’t have deep pockets and legal costs probably outweigh the benefits. Pretty cushy deal.
Because of the terrible reason Trump gave for the commutation (perpetrator always votes Republican), this already makes DJT, and by extension MAGA, look bad to center-right voters (see National Review takedown). There is no benefit to society by stepping on that.