I believe no-one here at the time knew how aggressively he was being treated. If we had known I'd like to think people would have been more supportive.
In fact I think the notable thing was how very quiet the reaction had been. A lot of CFAA cases that did acquire wide acclaim (including places like HN) were for things like accessing the "wrong" publicly-accessible URL, or finding security vulns and getting in trouble for just trying to let the organization know that they were vulnerable.
In this case it seemed to me there was a strong sense of "huh, this guy [Swartz] actually did break into a network, and server closet too" and therefore there was not nearly the outcry as we'd seen for most.
It is disturbing that some are still claiming he broke into the closet when it was unlocked [1], and others here apparently believe that changing your MAC address should be enough to trigger federal charges.
[1] Swartz broke into a closet in the basement of a building at MIT http://www.volokh.com/2013/01/14/aaron-swartz-charges/
As soon as the information was transferred over interstate communications channels to Boston the jurisdiction would have been properly Federal in nature.
If it is also a state crime than the attorney's offices can negotiate as to which (if any) will prosecute but the Constitution makes it very clear that the Federal government has primary jurisdiction in this situation.
It is true that most Federal crimes are more severe than state (since they necessarily tend to involve more serious offenses by their scope alone). But had a "misdemeanor-level" CFAA-like Federal law been available it is possible that it could have been used instead of the actual felony-level CFAA. I'm not aware of any though, as far as I can tell it's either CFAA, nothing, or the prosecutor can perhaps try to get extra-inventive with other law on the books.
Either way though, changing a MAC address was not the only thing Aaron did. Your point about the server closet not actually being locked is well-taken, but you bring discredit to your own plea for accuracy by implying that the MAC address is the only reason any sort of charges were levied on Aaron.
Thank you for the explanation of the difference between Federal and State offences though.