I've opted in to Australia's version of the biobank knowing that it's inevitable that it will be leaked some day, I think the data is so valuable in perpetuity that it's worth it. I remember Ben Goldacre has been working on how to make data more accessible in a safer way to (in part) avoid this very thing, but I haven't heard much of it since [0]
[0] https://www.bennett.ox.ac.uk/blog/2025/02/opensafely-in-brie...
I have huge problems with Goldacre's project because that project has never been disclosed to the general public let alone some form of opt-in/opt-out.
I like their idea of an audit log of analysis runs -- beyond transparency, I'm sure it'll help future researchers know how much iteration is needed to work with the messiness of medical records...
I'm also amused (in a good way) by the fact that SAS isn't supported as an analysis platform...
This is the right mindset. Securing huge piles of heterogeneous data while giving PhD students the freedom to "play" with it are quite conflicting goals.