It's quite a long list of exclusions.
They aren't exclusions, only questions that need following up and discussion with someone knowledgeable. Something that can't be assessed with a simple yes/no on a website.
I've had a skin graft and been on heavy anti-inflammatories that previously excluded me from donating (15 years ago). I've lived outside the UK for longer than 6 months in one go (lived in the US in 2001). I'd also been out of the UK in the last 12 months (France).
Most importantly I'd spent 2 months traveling around South America in the last 12 months (Chile, Argentina and brief visits to Uruguay and Brazil). The Brazil trip took me into a malarial zone.
So that was 3 or 4 questions that get me "rejected" according to the online test.
All this triggered was someone asking me about it in person, asking if I'd had any problems, or slept in mud huts (Chagas disease and Malaria) and then deciding that it was still ok since it been 10 months since I'd been back from S America with no problems. They just submitted an extra sample of my blood for a Malaria test (as well as the usual things they test for).