I’m from Mexico, and the most used chat application is WhatsApp. It’s used for EVERYTHING. I use Telegram only for contacting my family members (both my parents and my brother). They also use it only for this family chat. All my (and their) contacts use WhatsApp instead.
Now with the news that Telegram will collaborate with Twitter, I feel that I should delete it. Not that Zuck is any better than Musk, but still…
Also I don’t think it’s worth the effort to teach my parents yet another messaging app, like signal.
As for WhatsApp, it’s true that being Meta they collect everything they can, mostly metadata, but don’t they still implement the same end-to-end encryption as Signal? So, at least the actual content is your messages and calls should be truly private, i.e. out of reach even of Meta (and let’s say, all of this using a phone with no google e.g. graphene or lineage or calyxos). Please correct me if I’m wrong.
I don’t know about the algorithm but the app could be able to read the contents and open them up to scrutiny by meta. I wouldnt put it beyond them, especially since the signal app is open source and whatsapp isnt so we wouldnt know.