It just takes so much extra effort for your hearers. You’re placing the bulk load of information dissemination onto their shoulders, when – if your content is already full – you want to make it as easy as possible to hear and understand.
It’s not that you should never use the passive voice, just rarely. Why would you want people to waste their brain’s limited attention to untangle your sentences?!? Work harder at your script. Say it simpler so they can give their attention to the implications and meaning of what you’re saying.
So… I’m not saying the passive voice should be avoided. I’m saying you should avoid the passive voice, for the sake of your hearers.