I can confirm that id detection still does not work on e.os t-1.21 with my fairphone 3.
Seems like it’s a common problem.
I tried many, many times placing my id card just at the right position. Without success.
I just tried this again and it actually worked much quicker than when I first installed the app. I positioned the (German) ID card against the lower half of the FP3+ backside, with the card’s one slim end covering the lower 50% of the FAIRPHONE letters, the other slim end more less aligned with the FP3+ low end.
It worked both with the photo outside as well as right against the FP3+ back. I did not need to take my FP3+ out of the protective case for recognition. My device is on /e/OS 1.21 T (dev).