I don't use WhatsApp (or Telegram) but I see it as a huge win that people are switching away from Facebook. Breaking the iron grip of FAANG is the first step needed to getting Average Jane to switch to something safe.

Default E2EE from Facebook is as trustworthy as using their VPN for privacy. "We don't share between WhatsApp and the rest of Facebook" reminds me of "I didn't have sexual relations with that woman".