The Google Contact API is considered obsolete as of June 15, 2021. The Domain Shared API uses the Contacts API to edit directory contacts. Will a solution be available to replace the contacts?
Domain Shared Contacts API won't be affected by Contacts API deprecation, and it will still be available for use after June 2021, according to the deprecation announcement:
Please note that the Domain Shared Contacts API is not affected by these changes.