thank you for the reminder. I keep needing to do this.

This isn't actually about your phone number.

I got the same message because I do have my phone listed in there, but don't have a recovery email address listed.

With all do respect friend, I'm assuming most of us here that really care about privacy ditched Gmail very early in our privacy journey. I think virtually every policy Google enforces, including phone validation has some element of data collection in mind. We can debate whether providing the phone number is an information grab or a security measure, but I'm fairly certain it's both to some degree. If one cares enough about privacy to post in this community please start looking for a privacy respecting email provider, then start abandoning Google services like the plague at a pace you can tolerate. Don't move too fast on your journey, the inconvenience is rough, but liberating your digital life is priceless one step at a time.