Because in order to operate a business (or any organization), you have to at some point decide on a group of service providers and other 3rd parties that you trust. For most organizations, trusting a major videoconferencing vendor is going to be within their risk tolerance. For some organizations (or for some use-cases within organizations) this wouldn't be acceptable (or perhaps trusting Zoom wouldn't be acceptable, where a different vendor might be), but at this point you're starting to stray outside of Zoom's target market and into a set of more specialized requirements.
Defending against sophisticated state-level actors goes even further beyond the requirements of most businesses. Unless you had a specific reason to believe that you were a target of such actors (dealing with national security, or matters of significant national strategic importance), you couldn't justify investing much resource into such defensive measures.
Defending against sophisticated state-level actors goes even further beyond the requirements of most businesses. Unless you had a specific reason to believe that you were a target of such actors (dealing with national security, or matters of significant national strategic importance), you couldn't justify investing much resource into such defensive measures.