The arrest also came quite shortly after the company issued a warning about having hacked creatures on its cloud storage service, Pokemon Home. The normally expected outcome of getting caught is getting banned from the service. So it does feel a bit over the top for it to end in an arrest.
That being said, this arrest does come a month after someone was arrested for forging ice cream sticks to will lotteries of Pokemon cards. It does appear that the game series attracts not only the most desperate of fans, but also the harshest punishments.