I want to delete my Apple ID account and leave the Apple eco-system forever—because of reasons. But it would be a pity if all the purchased apps, books and music were lost. That's why I would like to transfer purchases to another accounts.
I know this is an old question and all questions I found about this very topic are 7–9 years old. It seems Apple does not want us to make it possible. Has the situation changed since then?
No.
The situation remains unchanged. There is no method to transfer licenses for app and media purchases between Apple IDs.
Even a legacy contact in case of an account holder’s death gets no access or license to these purchases.
Certain information, like movies, music, books, or subscriptions you purchased with your Apple ID, and data stored in your Keychain, like payment information and passwords, can’t be accessed by your Legacy Contact. Learn more about the data your Legacy Contact may be able to access.
The only solution would be to set the other user up in Family Sharing, but that will make one of the 'family' responsible for all future purchases.
People in your situation should plan to retain secure access to your Apple ID if you hope Apple changes this policy and are not ready to lose access to past purchases.
