While you may be the "visible culprit" - I'd hardly say you're at fault. The action you're attempting is not a "send email" action, even if the API provider has decided that it should send email notifications.

The implementation you'd probably want to see is for the API's email notifications to be batched if more than small-n trigger within a short period of time. Then the end user gets a notification that "1700 updates have occured" instead of getting 1700 emails.

The API should also be set up with exceptional event detection. Spikes which are several orders of magnitude above normal should get paused in the task queue and flagged for immediate manual review. Users do things you don't expect.