Well, you are confusing civil and criminal law. I assure you winning a laches defense is no sure thing, nor does it necessarily win the entire case, it is more likely to only limit the period of the offense for which the plaintiff may seek damages.
And being a passive participant in Linus discussion is no tacit license to your copyright rights over what the GPL already offers. If Linus really wanted that, he'd have to call for opposition, and remove works of opposing parties from the kernel.
