Nintendo, while aggressively litigious, do so to maintain the value and exclusivity of their IP.
Their games also never go on sale, and all sell really well over time, unlike many releases from other publishers.
The result is that Nintendo are able to release a solid cadence of high quality, first party games free of other forms of aggressive monetisation, maintaining the value of the games as art.
Came here to say this. Their pricing strategies definitely are justifiable but their petty lawsuits do little-to-nothing to protect their bottom line.