Why twitter acting like the first Mario Movie didn't have a plot? It did have a plot it was just simple and straightforward and it was still a great movie. You don't need a detailed narrative to have a good movie
Fun fact: Every digital game you have ever purchased on any Nintendo platform ever is still available to re-download. They first started offering such games on the Nintendo Wii, that released in 2006.
Any game bought on Switch or Switch 2 digitally, or via key-card - will likely still be available to download 20+ years from now.
It's not a problem until it actually happens. ATM, nothing has ever indicated we need to be worried from NIntendo.