Pre-pandemic, I used both Bluejeans and (Blackboard.com's) Collaborate Ultra. Bluejeans already let you use your phone years before. Neither required an account for anyone but meeting organiser. Collaborate Ultra doesn't even have a native app (as far as I know), it only has a web app.

I have no idea why so many folks like Zoom; I find it to be less useful than either. E.g. using external monitor with different resolution is handled very poorly.