The website claims that Nissan (the guy)'s business existed before Datsun became Nissan. I think there ought to be some kind of prior art for trademarks as well. It is not fair that a business suddenly not be allowed to use their trademark (even if they fail to register it) just because someone else registers it.

They might have. No definitive answer to that alternate timeline.

If his name was France, his use of the domain would have been more defensible(depending on what he was doing with the domain).