Don't know bigbluebutton but at least among Jitsi and Google Meet, Wire is an alternative that is open source and end to end encrypted. They just don't make it

Don't know bigbluebutton but at least among Jitsi and Google Meet, Wire is an alternative that is open source and end to end encrypted. They just don't make it easy to host your own, for that I guess Jitsi is the best way to go.