I'm not sure that placing free long distance calls isn't harmful to the org whose infrastructure you're using for your own benefit, but 2600 (Hz) is a respected hacker magazine and phreaking and Cap'n crunch whistles are seen as cool
Hacking the Internet Archive and only placing an alert with a provocative message, I could see my teenage self do that. My judgment of the character is going to depend on what it turns out they've actually done
Of course, my grown up self (or late teen also, as I've done responsible disclosures back then as well) would rather have seen them do a coordinated vulnerability disclosure, but alas, I just meant to remark upon the "special place in hell" for not having a plan or motive bit
*Edit:* wait, I just saw in the article (I opened the thread before the link was changed) that this quote refers to a DDoS, not the alert() message that the thread was initially about
> the site was experiencing a DDoS attack, posting on Mastodon that “According to their twitter, they’re doing it just to do it.
That's indeed just destructive and not related to (hacker) curiosity...