There is no real difficulty switching. At work, we use multiple solutions, including Zoom. Zoom has been the most reliable. If one was more reliable or had a killer feature, we could switch in an instant.
Slack has chat history that makes it difficult to switch. What does Zoom have?
Sounds like you don't work in a large organization with lots of standing meetings and extremely non-technical users. That must be nice.
Many large companies have lots of extremely valuable non-technical users who can just barely figure out how to follow step-by-step instructions to setup calls with even the most point-and-click interface. The switching cost there is extremely high.
The top of page 21 in the first set of SEC documents:
Quote " Many governments have enacted laws requiring companies to provide notice of data security incidents involving certain types of personal data. In addition, some of our customers require us to notify them of data security breaches. Security compromises experienced by our competitors, by our customers or by us may lead to public disclosures, which may lead to widespread negative publicity. In addition, we have a high concentration of research and development personnel in China, which could expose us to market scrutiny regarding the integrity of our solution or data security features. Any security compromise in our industry, whether actual or perceived, could harm our reputation, erode confidence in the effectiveness of our security measures, negatively affect our ability to attract new customers and hosts, cause existing customers to elect not to renew their subscriptions or subject us to third-party lawsuits, regulatory fines or other action or liability, which could harm our business. "