If this turns out to be true, then we can conclude two things: 1. It's incredible that the security of Twitter allows for a solitary 17-year old to gain full access to (any) account. 2. This also explains why the profit of the hack was 'only' ~$100k. Many speculated about how incredibly valuable such a hack could be and how much more a group could have profited from this hack. Using it for two hours of bitcoin scammi…
Someone else spoke to him being a teenager as not especially relevant, and I agree; it dismisses teenagers somewhat.
You're also falling for a selection bias. Twitter is a big target and likely stops attacks like this daily. This is just the one that got through, and probably more because of luck than skill.