How about KYC/AML (if you like cryptocurrencies)? And why it became so complicated to register an e-mail or account in messengers account or web-page in social networks without phone number? I have lost few really great friends because I've lost an access to my phone (literally burned in fire with a sim-card) bonded to the telegram account, for example. Also, I am really suffer for neediness to have a smartphone for daily needs like ordering a taxi instead of just to phone and to pay cash. These examples are just from top of my head, there are plenty more.
