Hence, we came up with save2cal.com. This javascript app allows you to create your event and share the link with your friends. When the link is clicked, it opens the calendar app with your content prefilled such that they can directly save the event. Happy to hear your thoughts!
One thing we'd love to change is making the links shorter. We don't store anything on the server side and encode all entered information in the string and decode it in the browser when the link is clicked. Then we generate the calendar file and open it. Ideas to make the link shorter? We could create a shortlink mapping, but then we would need to store data. We don't want that.
An example: https://save2cal.com/v1/index.html?data=JTdCJTIydCUyMiUzQSUy...