The concern isn’t access to the flight status data (or even your data, which is most likely encrypted these days), but theft of service you paid for, by another passenger on the flight (you would probably at least get kicked out/experience issues with your own connectivity, and might worst-case be blamed if something bad happens using the connection you bought).

I’m confused, none of what you’re describing is part of the article.

It's responding to the scenario described in GGP.

Ah, does that hack still work though? I would be surprised if it did, since the story was from years ago.

I used to play with IP-over-DNS, which more or less worked on an awful lot of these plane wifi systems. Haven't tried it in the past couple years though; it's always slow the point of barely being usable. You can probably get your mail via IMAP if you're patient and nobody's sending you large attachments, that's about it.