I actually agreed with this until I saw the actual rule. The rule takes effect in 2027. It is not arbitrary and capricious to set a rule to take place a year in the future, when it requires planning and coordination by the members to manage rosters.
It was still an own goal on their part to not recognize that this was going to happen. Clearly there is no shortage of judges willing to embarrass themselves and the judicial branch and it only takes ones per state for the most part. But as egregious and embarrassing as the Chambliss decision was, this is actually worse. It's perfectly reasonable to take the position that schools need time to plan for rule changes, and to announce a rule that will take place in the future. It's absurd to take the position that there is no rational connection between the rule and the facts or that it's an arbitrary application of a rule to not apply it until it actually takes effect. But it's also absurd to pass a rule without taking into account that at least Auburn, Alabama, LSU, UGA, Ole Miss and probably plenty of other schools will be able to find a judge willing to take an absurd position for them.