[RandFan]

Most places now ask for #

Internet banking, google, Microsoft etc.

Some people dont like it and I sympathize with them.

[SmokingJoe]

The phone number is not a big issue. It's mostly for if/when you forget your password and need to get back on.
However, if it's a big problem, don't join social media then or use a throw away phone.
The point is, if you are already on Facebook/Google/YouTube etc, you already gave your phone number anyways.
If/when Trump moves to Parler, most of his followers on Twitter will follow him there, especially his millions of enemies on Twitter. They just can't help themselves.