I guess because it ends with "Sent from my iPad"? Still seems like an uncharitable interpretation considering that a "humblebrag" is a pretty deliberate thing.

Maybe he just wanted to remind himself of these things.

Steve Jobs was a complex person, yet he was nothing if not deliberate. It is indeed "uncharitable" of me, but I cannot read that "Sent from my iPad" as anything but the punchline that the rest was built around.