If the plethora of iCalendar email attachments I've seen over the years (despite not owning any Apple devices or using their software) is any indication, I'm no

If the plethora of iCalendar email attachments I've seen over the years (despite not owning any Apple devices or using their software) is any indication, I'm not sure that only being on Apple devices will be a significant barrier to people trying to coordinate stuff with this.