> In Telegram, E2E encryption is not on by default in chats (it is on by default in calls), and is only available for one-to-one chats (the so-called Secret Chats) and calls (including video-calls). Groups, independently of their size, are not E2E encrypted.

Correct me if I'm wrong, but isn't WhatsApp E2E encrypted by default for a while now?

> The fact that Telegram does not publish server-side code while Signal does has no impact in the security assessment of these services... Still, from a security standpoint either of them is a better choice than WhatsApp

So if WhatsApp published the client code it would be at least as secure as Telegram, maybe better because it has E2E encryption enabled by default?