For people saying it's as simple as Berian saying: "I don't want to be sponsored by Nike" It is also as simple as "Nike wanted Berian to be sponsored by them."
If the burden of proof is for Nike to show that they matched the offer, I think it is a very case for them to make. They would not be in court and we would not be discussing it if Nike thought they could make a blatantly lesser offer and have it hold up as a matching contract.
Nike is also the only side that stands to lose anything in this ruling. If the judge sides with Nike, both sides essentially win.
Deep down, I'm not buying that Berian has this much dislike for Nike shoes. He was trying to be Robin Hood for the Big Bear TC by securing them the New Balance sponsorship, which would mean greater resources for his coaches, teammates, and agent.
If he struck a deal with Nike, he is greatly reducing his marketing relationship with his team, which is another reason why track and field is so whackadoo. All athletes should think of themselves as independent contractors. The Nike deal was a fantastic one for Berian, and he likely would have received an even greater pay day after Rio.