Most people are locked in to it because change is hard and they don’t care that much about privacy.
WhatsApp uses Signal’s encryption and according to https://signal.org/blog/there-is-no-whatsapp-backdoor/ has no backdoor.
The privacy concerns are not that Meta will read your messages (because they can’t, as you mention), but the metadata they can read such as your details and who you contact.
“So, Facebook can track who sends WhatsApp messages, when, to whom, from which location (if a user allows), etc - but not the content itself,” Rykov says “This creates a privacy concern for people who want full anonymity. These people should consider using more privacy-enhancing apps like Signal, Threema, Wire instead.”
https://foundation.mozilla.org/en/blog/a-cheat-sheet-for-whatsapp-privacy/
the metadata they can read such as your details and who you contact.
Every provider of communication services can. Singling out WhatsApp in that regard makes no sense. Apple happily hands over metadata and iCloud backups to the FBI.
the metadata they can read such as your details and who you contact…Every provider of communication services can.
Signal does not, since they use Sealed Sender.
