This is misleading.
Nintendo signals it'll go after the 'Pokémon with guns' developer for taking a little too much inspiration from the company's hit game franchise.
www.pcmag.com
It's only recently come under official investigation as of less than 2 days ago.
Whether they sue them is very much "we'll see" at this point, as the investigation has only JUST begun. I know people have been in-game having fun for more than 2 days it's been under investigation for-- so it's easy to lose sight of that fact.
Simply put, this was only recently brought to their attention. Sit tight.