NASA's Artemis 1 moon rocket passes crucial fueling test

Whilst the fueling test was finally successful they had yet more problems with hydrogen leaks and seals not seating properly. NASA has decades of experience in fuelling rockets with liquid hydrogen, from at least the days of the Saturn V (liquid hydrogen was used on the 2nd and 3rd stages) , through the days of the shuttle (which used the same engines that are being used on the SLS), so a bit surprising that they've had so many hydrogen leak problems with Artemis 1. I wonder if the design of the quick disconnect coupling used on Artemis 1 has changed in any way from that used previously, or whether in the time interval since the last shuttle mission they've lost a bit of expertise as people have moved to other jobs or retired?