The thing is, the “software” actually is open source, so you can tell how data is requested from your smart ID. The german government ID has an explicit function for age verification that does not provide any personal information.
https://github.com/Governikus/AusweisApp2
However it is probably hard and costly to get certified to use any of those functions as a service provider.
This one will additionally use user submitted titles and thumbnails when available instead of just random ones.