so? ToS is not the law! Nor can you use the CFAA here. It is not hacking. In addition, the operator lives in a jurisdiction that does not respect an American corporation C&Ds, what happens? Instagram has no legal ground to start an extradition treaty because somebody is scraping them lol.
You think Instagram is going to get FBI to bust doors in Mogadishu or wherever the operators are?
Might be an issue if you are in the US or West since its behind a walled garden (you need to authenticate to access) but you do not need to pay for it, nor are new registrants restricted (they have access to everything) so its a public website that forces user accounts. The best Instagram can do is throttle or ban those accounts scraping.