Like you said, these are appeals - not initial claims. That means they're cases in which the court has already reviewed the fairly clear-cut criteria for awarding benefits, determined that they are justified, and has proceed accordingly. Indeed, a court that reverses itself 36% of the time seems remarkably open to appeal by employers.

As far as the 64% of appeals that are rejected are concerned, it IS flat out wrong to say that these are all justified dismissals that they employer had to pay for anyway. After all, this figure also includes cases where employees quit for cause (e.g. flagrantly abusive work environments, failure to pay wages in full and on time, efforts to avoid paying unemployment claims by radically demoting or cutting hours instead of laying off, etc.), as well as cases in which the termination was wrongful, and likely to do lasting damage to the employee (e.g. by way of demonstrably slanderous performance reviews, for refusing to engage in abusive or deceptive practices on behalf of the employer, etc.)

You're also disregarding the way incentives function here. Since the employer is on the hook for damages - and the cost of an appeal is trivial - they have a strong incentive to fight, even in cases where they are monstrously in the wrong. Indeed, HR people will tell you that they automatically appealing everything, no matter what, as a matter of standard operating procedure. The idea is that by developing a reputation for reflexive fighting, they can use the notoriously slow pace of justice to delay payments for the better part of a year. Accordingly, people with limited savings who simply want to get the hell out of a truly unbearable situation can't count on unemployment insurance to finance their job search. Instead, they have to line up their next job before they quit their current one, rendering the question of unemployment moot.