Many in the crypto and privacy community mistakenly trust Telegram because it’s “end to end encrypted”, but there are huge issues including not hiding the metadata, censorship, centralization, and phone numbers.
Send this video to your friend that asks why you won’t join:
https://video.simplifiedprivacy.com/why-telegram-sucks/
It does NOT cost money on F-Droid. You don’t even need to install the market itself, you can get the app from F-Droid’s website (though then you’d have to check for updates yourself). For me, it was a chance to get mom to F-droid.