i think i have a xf0x9fx91x8cperfect solution for this.
Let me explain the issue, I have an iphone 6 which is now 5 years old and in all this time i have changed multiple jobs, i had a company exchange account and at some point all my contacts were being saved into that account. i moved on, they deleted my account so i could not login and my most of the contacts lived in that group. It complained about the password to that exchange account which i ignored and it still worked. But comes 2020. i move on to a new iphone, i realise my icloud can not help, itunes is out of game no more even supported on catalina ios. I came across this app on apple store for iphone MCbackup it works wonder, no setup, no fee, no subscription, no activation nothing I simply gave access to contacts, it copied everything from all the groups and gave me option to send a csv or vcard which i then sent to my email. Afterwards i now use only gmail for contacts and then easily imported this csv into it.
Now all historical contacts are working for me. :) i hope this helps you all.