Vice versa you can cause your opponents so much trouble with lawsuits that - even though you don't win them - you are better off than them afterwards.
In this case, it appears that Cyrix came out on the other side of the battle in a better position for their win. It would seem it was their later acquisition by National Semiconductor that eventually snuffed them out.
It would be different if the lawsuit is so expensive that one party could go bankrupt due to it.
This isn't about right and wrong. It's about money. Who has to pay how much to the other party? Both parties think they are better off if they fight. Both parties think they could win money in the end. It's a gamble in the courtroom.