I'm not sure it does make onboarding trivial. How do I join WhatsApp/Signal/Telegram with an iPad or iPod Touch? A laptop? A handheld gaming console like a PlayStation Vita? I can't sign up for any of these services without a phone and a phone number. Sorry, my phone number is a legacy communication layer that should just be replaced by the Internet.
When I went to Brazil last year, I switched the SIM in my phone from a UK one to a Brazilian pay-as-you-go SIM. WhatsApp said "oh, you've changed SIM, do you still want to use your existing (UK) number?" I guess that's okay behaviour. Does Signal do this? Does Telegram do this? I don't know. I have to keep track of what goes on when I change my SIM. That's a layer violation. The network I use to access the Internet shouldn't affect the behaviour of my messaging app. If I'm chatting to my friends, it shouldn't matter whether I have a UK SIM, a Brazilian SIM or no SIM at all.
What if I move from the UK to Brazil permanently and get a long-term mobile contract? Shall I still use my UK number for WhatsApp/Signal/Telegram or should I use a Brazilian one? Will I lose my contacts? Will they stop being able to talk to me because my number has changed? I don't know. That's pointless administrative overhead.
What if I let my pay-as-you-go number go stale? If you don't make a call or text for six months or so, the mobile network may disconnect your number. At some point, they'll reassign that number. Can that person now access my WhatsApp/Signal/Telegram? Okay, well, maybe we put a secondary password on it like Telegram to stop the account getting hacked if I lose access to the mobile number. Now the person who inherits my phone number can't set up their own Telegram account because I'm already "squatting" the old number.
This is ridiculous to me. It's like an Internet without DNS, where we have to manually keep track of each other's IP addresses. Nasty legacy phone network shit. Don't need it, don't want to deal with it.
Yeah, I agree with you. What I should say is that it makes onboarding trivial for the most common case, and they explicitly don't care about any less common cases (even if they are not all that uncommon).
When I went to Brazil last year, I switched the SIM in my phone from a UK one to a Brazilian pay-as-you-go SIM. WhatsApp said "oh, you've changed SIM, do you still want to use your existing (UK) number?" I guess that's okay behaviour. Does Signal do this? Does Telegram do this? I don't know. I have to keep track of what goes on when I change my SIM. That's a layer violation. The network I use to access the Internet shouldn't affect the behaviour of my messaging app. If I'm chatting to my friends, it shouldn't matter whether I have a UK SIM, a Brazilian SIM or no SIM at all.
What if I move from the UK to Brazil permanently and get a long-term mobile contract? Shall I still use my UK number for WhatsApp/Signal/Telegram or should I use a Brazilian one? Will I lose my contacts? Will they stop being able to talk to me because my number has changed? I don't know. That's pointless administrative overhead.
What if I let my pay-as-you-go number go stale? If you don't make a call or text for six months or so, the mobile network may disconnect your number. At some point, they'll reassign that number. Can that person now access my WhatsApp/Signal/Telegram? Okay, well, maybe we put a secondary password on it like Telegram to stop the account getting hacked if I lose access to the mobile number. Now the person who inherits my phone number can't set up their own Telegram account because I'm already "squatting" the old number.
This is ridiculous to me. It's like an Internet without DNS, where we have to manually keep track of each other's IP addresses. Nasty legacy phone network shit. Don't need it, don't want to deal with it.