Like backing up data, having a contingency plan is important. Even if you like zoom because of certain features, having a backup service you can use in case of emergency is important. If everyone knows beforehand "which link to try if zoom is down today", then it is merely an inconvenience instead of an emergency.
Yep, that's what I do, and work is easy to coordinate, but some other social events or organizations with inexperienced non-tech people don't have slack and don't think to check their email. It is easier for them to have a pre-specified backup option.
