Emails can be simple - mine is $firstName@$lastName.me Tbh phone numbers are quite long and if people can’t remember 4 digital pin… Still you can generate qr code mailto: links

I still believe that mailing lists are the best technology which has been both decentralized in the meaning of the identity ( which you can verify with gpg ) and storage. While I like many other things like simplex, lemmy, to some extent matrix and so on, still mailing lists rock nowadays ( note: please consider 2 criterias i meant - distributed identity and storage)

I’ve once bought lifetime service - couchsurfing. It didn’t stick foe less than 1 year. I have second life time account for 2600 magazine but still I’m skeptical to “life time” promotions

There is: mdiscs. Allegedly 1000 years durability even in Blu-ray format. Should be good enough for most important things. The best tapes AFAIK 30- 100 years