Yes, one report generated for a single account equates to one request via the AdWords API. However, you may try out the
Parallel Download Report (other languages are also available in the link) that allows users to generate reports for all the accounts under an MCC in multiple parallel threads.
Please note however that this feature is subject to the limits stated in our
rate sheet. Should you be required to generate more than 1,000 reports per day, you may opt to
upgrade to standard access (if you currently only have basic access). I hope this has been helpful.