I just want to throw in my attempt at eli5 as I didn't really see one that I thought was clear.

Novak was appealing the Minister's latest decision, claiming it was an irrational or unreasonable decision.

the court has no say on whether the decision is right or not, they are simply making a statement as to whether the Minister made an irrational decision.

the court clearly decided his decision was not irrational. now to be clear, the court isn't answering the question of whether or not the decision was the best one, or even a good one.

they're simply stating that the way the decision was made, was not in an irrational way. or conversely, that somebody (the Minister) could have rationally come to the decision that he did.

and obviously, that would be very hard to prove otherwise, and it was always going to be very hard for Novak's lawyers to win this final appeal.