It's cool because in a small but poignant way it represents how Zuck was able to build his company w/o kissing Wall street's ass. So many CEO's tactics are driven by quarterly earnings. By keeping his hoodie on and not flying out to New York to ring the bell, Zuck kinda saying fu off to all that.
If that blue Nasdaq button embodies short term, profit driven thinking, it's neat that the engineers were able to hack it and bend it toward their will. It's a poetic hack.