Definitely overthinking. I personally like having the ability to see "events I'd like to attend" in my calendar. Users who don't like this can decide not to subscribe, or use an alternative calendar app, or learn how to hide/show specific calendars in their existing app.

If you have too many events, than probably creating separate webcal feeds for categories makes sense.

There's even sites that do the opposite - instead of providing a static ICS file for a "single event", they'll provide a webcal feed so that they "update the event" OTA in case anything changes. That is quite annoying tbh.