Haniyeh earned his Specially Designated Global Terrorist title on January 31, 2018. A company caught hosting terrorism-promoting content can face company-ending consequences. Executives have been sent to prison for turning a blind eye to doing business with sanctioned countries. Instagram was probably complying with these regulations.
Punishing Instagram for complying with the law puts Turkey into a precarious position. It’s an open secret that they offer cheap rubber, steel, and other raw materials because they’re willing to lie on forms and act as a conduit for Russia and Iran to bypass sanctions. Too much attention on sanctions programs and Turkey in the same sentence can potentially end that part of their economy, which they can’t really afford right now.