I feel like it's still important to remember the numbers of some important contacts, so you can actually call them using somebody elses phone if yours dies or breaks. But I suppose not many people would bother

Lol, not only do I memorize phone numbers of family members, I did my parents taxes so often, I can memorize the social security numbers of all my household members and all their birthdates.

Also I still remember addresses I used to live in.

We didn't memorise numbers! We just remembered them after having to manually dial them a hundred times.

That skill morphed into remembering user names and passwords.

Eh even before the Internet people had other tools to help with this. Physical books with people's addresses and phone numbers. Specialized holders for various business cards. Yellow pages and white pages. I suppose a lot of incidental memorization is lost but I don't think it's really a skill lost so much as the tool changed.

And those tools pre-date the invention of the telephone, so it's not like people spent hundreds of years memorizing phone numbers before writing was invented.

Why wife's phone number is 'babe' and ill die on that hill.