It seems like cloud save implementation will be quick and painless.
We know that the Nintendo Switch will finally get cloud saves (the only method of save management the system will have) with the upcoming Nintendo Switch Online service, but worryingly enough, we don’t actually have enough information on how it will work. And with Nintendo’s statement that it will work with “some games”, people have been bracing for the worst, and expecting patchy implementation of the feature.
However, it doesn’t seem like that will be the case — it seems like the Switch will automatically add cloud saving support to all existing games, and that the developer will have to actively opt out of that, according to a report by Nintendo Life. Apparently, that will also apply to upcoming Switch games — developers have to actively opt out of cloud save support, and they need to justify their doing so with a proper reason as well.
So on the whole, it sounds like unless your game could be compromised by save backups (so something like Animal Crossing or Pokemon), it should support backups on Switch just fine.
The Nintendo Switch Online service is due to launch later this month.