Yeah, a decent litmus test is if you sign into a service from a new device and without much effort all your chats/messages/history or whatever is there, the security is weak.

I got off WhatsApp years ago so I am not sure what's changed but back then if you signed on from any random browser, it was able to sync everything instantly and you'd see all your messages. This was after they claimed that it was E2E encrypted. What was explained to me at the time was that you share your encryption key with Facebook and hence the syncing.

Chat backups are end-to-end encrypted now. You're right that it wasn't encrypted for a long time though.

I'm not claiming it's the ideal solution. I'm claiming it's much better than lots of other things that came before. There's no point in having a perfect solution if the people I know don't use it. Everyone I know uses WhatsApp. It's a fact that life could be much worse than it is. They could be using SMS.

I didn't know this, and it blows a pretty big hole in arguing for WhatsApp as some kind of E2E paradise.