That is simply not correct. With properly implemented E2EE, you can communicate confidently over a completely insecure channel. You could post the entire data stream publicly on the internet with no loss of privacy.
What do you dislike about current E2EE?
However, on the WhatsApp webpage, you can find the E2EE hand-waving that I was alluding to: https://faq.whatsapp.com/820124435853543
"WhatsApp _considers_ chats with businesses that use the WhatsApp Business app or manage and store customer messages themselves to be end-to-end encrypted."
And later, they write that in many cases, Meta can actually read the messages.