I launched Upcoming Chats as a way to highlight Clubhouse App chat events since their really wasn't a public calendar at the time. It's all 100% automated. The events are found using Twitter's API. When someone shares an upcoming chat, the script finds it, pulls some OpenGraph / Twitter info for the event, and then adds it to the website. There is also a Twitter account that posts some of the most popular events coming up however it hasn't really worked as well as the website. https://upcomingchats.com