Reposting from "Gaming News" as it applies here as well:
Though a lot of games will have the feature by default when it releases, according to listings of Nintendo's website some Switch games will not be able to use the Cloud Save feature of Nintendo Switch Online.
Games that won't support the feature (So far):
SOURCE
In my opinion, while this definitely sucks, it's not completely unwarranted. Pokémon has had a history of people manipulating the save data to duplicate Pokémon and Splatoon 2 has had problems with hackers in the past so not giving them access to manipulate the save data/rankings makes sense. Similar arguments could be made for the 3rd party games as well. So, while it might not have been the best way to deal with the problem, it's not something Nintendo is doing just to spite players.
UPDATE: Nintendo confirms this decision was due to worries of save data manipulation/item duplication in online games
Though a lot of games will have the feature by default when it releases, according to listings of Nintendo's website some Switch games will not be able to use the Cloud Save feature of Nintendo Switch Online.
Games that won't support the feature (So far):
- Splatoon 2
- Pokémon Let's Go Pikachu/Eevee
- Dark Souls Remastered
- Dead Cells
- NBA 2K19
- FIFA 19
SOURCE
In my opinion, while this definitely sucks, it's not completely unwarranted. Pokémon has had a history of people manipulating the save data to duplicate Pokémon and Splatoon 2 has had problems with hackers in the past so not giving them access to manipulate the save data/rankings makes sense. Similar arguments could be made for the 3rd party games as well. So, while it might not have been the best way to deal with the problem, it's not something Nintendo is doing just to spite players.
UPDATE: Nintendo confirms this decision was due to worries of save data manipulation/item duplication in online games