I would like a new privacy setting for events that shows them as busy. This feature in etar calendar is called "confidential" e.g. Now it is only possible to choose between public (show all) and private (dont show event at all)

Hello,

DAVx⁵ (CalDAV sync app) supports both PRIVATE and CONFIDENTIAL, so implementing this idea would allow users to choose between those options. They have different meaning. For instance, when person A shares a Nextcloud calendar with person B:

* PRIVATE events of person A won't show up to person B
* CONFIDENTIAL events of person A will show up to person B, but only that time is busy, without details of the event

There are already calendar apps supporting this out there. Would be cool if Business Calendar 2 would be capable of PRIVATE and CONFIDENTIAL too.

On Android side, both ACCESS_PRIVATE and ACCESS_CONFIDENTIAL exist, so this should be really easy to implement.

See also:
https://www.davx5.com/manual/technical_information.html#event-classification
https://forums.bitfire.at/post/8966

I would like to see this implemented as well.
I use a nextcloud calendar which also uses those three categories for privacy. The confidential property corresponds to events for whcih only the time of the event and the fact that I'm busy are available to others, and that is what I would like to share with my co-workers.

Oh, sorry, I didn't know that, since I'm not using the google calendar. I've read somewhere, though, that you can set the option for each shared calender (in the google settings) whether the event's shall be shared as 'busy' or not at all.
In my enviroment (owncloud, caldav-sync, BC2, thunderbird/lightning), when I set an event to 'private' via the owncloud web-interface, thunderbird/lightning or BC, the event will not be shared, if I set it as 'confidential' (only possible via web-interdface of thunderbird/lightning), it will be shared as 'busy'.

I think you're wrong: in shared Google Calendar, your private events appears as "busy time" (without details) to people you shared calendar with...

No, "Private" means: Only the calendar's owner will see the event, to everyone else it will be completely invisible as if it was not there, even if the calendar is shared. With classification "confidential" one can share his availability to other users while keeping the events' details classified. In my case this is essential even besides scheduling a meeting with the user the calender is shared with.

Is not the same as "Private" in Google shared calendar?