@BenCotterill I've updated to 26.4.1, which dropped tonight, and my phone has decided that I'm old enough, even though my iCloud account is only 16 years old.

So they might have relaxed their restrictions somewhat; alternatively, it may be that I had a support issue open with them and the support staff saw me trying to take a photo of my passport.

So if you're still having issues, might be worth having a chat with support.