Explain the problem as you see it
Tana currently syncs all Google calendar events but there maybe be some events that I do not want to sync into Tana.
Why is this a problem for you?
I cannot speak to the original poster's request, having extra events in Tana where notes are not necessary can create additional burden on the UX and/or contribute to attention residue for the desired behavior Tana encourages from its users.
Suggest a solution
I have used Reclaim AI in the past and they have an interesting way of using hashtags in the notes section of Google Calendar events which tell Reclaim to ignore certain actions, add a travel buffer, etc.
If the '#nosync' hashtag can be incorporated to ignore the events from Google Calendar into Tana, I believe it would be a great solution for other users looking to do the same thing.