So as you might know the 3ds has been put out of production. It is reasonable to think that online closure will follow suit, along with closure of the wii u's online services as well. Although I'll put here why I don't think that'll happen. 1. The eshops of the switch, wii u, and 3ds all share the same network to some extent. When viewing your wish list on switch you can see wii u games and the like (remember when people thought you could buy 3d world on switch because of that?) 2. they all share the same funds and NNID system (to some extent, like user transfers I think) 3. It would be bad practice to close online because some games like splatoon have most of their content in the online portion of the game.