Notes

*Nobody* should feel comfortable providing their private phone number when signing up for an email account or another online service, because that phone number is linked to your personality, i.e., name and address. And if you give Google, Yahoo or another "trustworthy" service your phone number, your Google account is therefore linked to your identity. Every email you write could be traced back to your house. People complain about mass surveillance and then they provide service companies with their real identity. I don't understand why we play along with this.

And yes, it might be quite useful to receive a text message in case you have forgotten your password. Now, how was this problem solved before every provider wanted your phone number? There were security questions to which you would provide a custom answer. If you had forgotten your password but gave the right answer to the security question, you were able to reset your password. And except for some providers that forced their users to pick a pre-defined question like "What's your middle name?", it was a good system. Of course, I'm not saying that being able to receive a text to reset your password can't be useful. I do know that some people tend to forget their password along with their security answer and many other codes (except for their phone PIN which they need to receive the text, nobody forgets that). It's when you're forced to give them your number that you realize it's clearly not a service because they're so thoughtful but simply a surveillance mechanism.

As for the link between your phone number and yourself: In many European countries, it's now illegal for cell phone providers to sell anonymous prepaid cards. They have to be activated with your govt-issued id or passport. It's still possible to buy activated cards on Ebay, but that'll probably be stopped at some point as well.

I feel like many people just blindly play along. They wouldn't mind seing a black surveillance van parked in front of their house every day as long as it's not blocking their driveway.