it’s not at all like that, and i’m not sure where you’re missing the boat.
nintendo has ownership stake in the developers of all the titles we’re talking about. it would be like if valve turned off cloud saves on left 4 dead 1. you’d come in to comment how it’s turtle rock’s fault that valve turned off a feature that was implemented by valve on a platform owned by valve for a game published and developed by valve.
in this analogy you’re also playing on the steam deck, so the hardware is also built by valve.