I'm unable to figure out from the docs how to unauthorize a user's linked account and stop receiving events from their linked devices. Is there a request for this? Or maybe by invalidating the user's Oauth2 access/refresh token?
The token can be revoked either by the user via https://myaccount.google.com/permissions or by revoking the token by passing it to https://oauth2.googleapis.com/revoke
See https://developers.google.com/identity/protocols/oauth2/web-server#httprest_8