Associating phone numbers with IM identities is awfully stupid. The good old "register with just login\password, confirm with any email" was fine, and I remember people complaining about sites which required email confirmation, it felt disrespectful and spam-inducing.

Now, mobile phone numbers - that's literally the way to inform everybody offended by your opinions or just interested about your everything, at least of the "necessary for a successful murder" kind.

Does Telegram not send a verification code? (It's been like a decade since I signed up)

Seems like an easy solution. It's not like phone numbers are secret hard to guess numbers.

Given the huge popularity of WhatsApp I suspect warning people to not share their phone number is too late...

Phone numbers get recycled all the time. The best thing you can do really is keep the same one rather than changing

this reminds me of the you have been banned from Pyongyang memes

From my perspective, the digital realm should remain separate from our offline lives.

The idea that there was ever a "digital realm" separate from real life is pretty silly.