Huh? Many games have already received free upgrade patches, the paid ones generally include new contentHave they? I guess it remains to be seen when next gen rolls around and if they provide free visual/performance update patches for their Series games for the new system or not.
Let's also not forget BC and it's very cool and free features like auto HDR, FPS boost etc. again, Nintendo would never, sadly.
And bc on switch 2 provides automatic performance boosts to most games