These spam invites are a nuisance and it is nice to know there is a work around but why hasn’t Apple addressed the problem?
Sea
These have only reared their ugly heads in the past month or so using a useful app function. . . it's going to take some time to figure out how to filter out the spammers while retaining the utility of the invitation functions. Apple has said they are working on it. Just limiting invitations to people already in your contacts list is one somewhat unsatisfactory approach as it very much limits whose can invite to events.