Create anonymity of users

Meetings and Webinars: Names populate based on the user profile of the person joining. The attendee controls how their name appears because it's in the profile of their account.

Meetings: You can turn off the attendees ability to use video, but the name will still appear  consistent with the user's profile. As the Host you can change the person's name to something like "Attendee 1", "Attendee 2", etc. as people join.

Webinars: Only the panelists can see all the names of the attendees. If you really want to take advantage of anonymity, run your session as a Webinar. https://support.zoom.us/hc/en-us/articles/360000252726-Roles-in-Zoom-Webinars#:~:text=Panelists%20are%20full%20participants%20in,sharing%20your%20screen%2C%20and%20recording.