The Nintendo core fanbase yes. They will buy regardless.
What about the casual gamers who make up a massive majority of their user-base.
In fact every console user-base.
Kinda this. It moves them in the direction of soaking up all the sales they can get before moving on to discounts.
But if they are pushed to do that, they become like other publishers where everyone knows they can just wait for the discount. Removing even more people from the $80 group.
Has potential to backfire.
Edit: After writing this I got in the shower and something came to me there lol. Last gen, Nintendo priced games at $60 and in keeping true to their "one price" policy, didn't increase prices even with the industry standard and inflation. Sure Mario Kart never got a discount but they never adjusted for inflation either and ate it.
Knowing full well that they can never increase the price of the game, they may be hedging the standard of their most popular one against the same situation. They always have the opportunity to do vouchers, bundles or a very rare sale to bring it down, but can't raise it beyond the initial ask without immense pain, and see this as an evergreen title for the life of the system.
Who knows, maybe the eco gets so lopsided that normal games become $90-100, and by holding at 80 it becomes another veiled price decrease like last gen.