I came across this thread while looking for the answer to the same question @Dan Kaplan` had. In fact, it seems that this comes up a lot. Here are just some of the examples:
https://techcommunity.microsoft.com/t5/microsoft-365-developer-platform/ability-to-update-or-create-an-event-without-sending-a/idi-p/2335070
https://stackoverflow.com/questions/57548606/how-do-we-suppress-notification-emails-for-events-created-through-ms-outlook-cal
https://stackoverflow.com/questions/58094438/update-and-delete-calendar-event-without-sending-notification-to-attendees
https://stackoverflow.com/questions/45671589/outlook-365-api-disable-automatic-email-send-when-creating-calendar-event
https://stackoverflow.com/questions/60846937/restore-calendar-event-without-sending-notification-to-attendees-using-ms-graph
This question was presented over a year ago by @Aleksandar (Saša) Gargenta
Event management is a core requirement for business operations. If the feature to suppress emails on event creation/updates is not available via the Graph API, can you direct me to where I can submit this feature for consideration?