0. Software is supposed to be designed to serve me; it's not my job to find workarounds for shitty design. This is a shitty design, and therefore people are criticizing it.

1. It's annoying because I already have all the birthdays I want on my iCloud calendar; it's creating a pile of duplicate events.

2. It's annoying in 3rd party apps when you hit a show/hide all calendars button, but you never want to see the Birthdays calendar.

3. Some 3rd party apps don't let you show/hide calendars in general, and this isn't a writable calendar, so it's doubly annoying. (Yes, this is shitty design too.)