They aren't even accessible to the 80% of the world that is using Android. If they were, they'd get live captioning 'for free' because Google has brought live captions to the OS level, so any app / website has live captions now since it's an accessibility option and an OS level overlay. Furthermore, being on iOS only also makes Clubhouse inaccessible to people with lower incomes and fixed incomes. Equitable and inclusively designed products should be accessible to everyone.