Perhaps because non-programmers (aka civilians) don't know what GitHub is, and it's difficult to explain.

Perhaps it's interesting to reframe in a language that affect most people:

"Linux development halted by ciberattack!!!"

That's not completely true and too linkbaity, especially with the three bang sings. Is there another huge mainstream project hosted there?

Another linkbait:

"Hackers break hackers site!!!"

Not so appealing to most people, but you can exploit curiosity. Also, you'll get a lot of complains about the incorrect use of the word "hackers" in both positions.