Concept:
Only test questions are allowed...
like python if statements....

NOT ALLOWED:

• What is this person's name?
• How old is this person?

ALLOWED:

• Is the name James?
• Is the person over 18 years old?

The answers are short and direct....
TRUE
FALSE

Is the name James? TRUE
is the age over 18? FALSE

If the user wants to, they can encrypt the data....
but depending on the amount of data, it will take a while

The user MUST agree to share more details (like the direct address of the place of residence)

all requests use a unique, randomized request ID, so (if the user wants to encrypt the data or the retrieving took more time as usal...) the response is stored on a public (government-provided or generally trusted) server
so that the data can be retrieved once
after the one-time retrieval, the data set and the response are deleted

furthermore, only the answer is stored on the server and not the question itself

so you cannot get any information from a (yes, no) question
but only in connection with the question
which is known to both the requester and the requestee

the encryption is done with RSA key pairs...

sometimes special answers are required for comfort reasons

An example
amazon could ask for the direct address, so you don't have to type the address anymore
(which of course must then only be retrieved locally so it is not allowed to upload it to an answer server)
plus amazon needs a certificate for this feature
(to make sure that we give our address to amazon and not to a scammy amerzun website)

here are some more examples

Pornhub...
don't need to know my name or my age....
pornhub only needs to know if I am an adult!

amazon does not need my passport picture
but maybe we should give my passport picture to the delivery boy
so he knows what the recipient looks like? (must be an opt in option)

Any other ideas?

please suggest them

Thanks to The Morpheus for give me some ideas:
https://www.youtube.com/watch?v=VrIFPBNifqc
https://www.youtube.com/@TheMorpheusVlogs