It's merely better than nothing. If you've been waiting for discounts on older first party games, you've already had multiple chances to buy digital versions for $40 instead of $60, because Cyber Monday, Christmas, Mario Day and Easter were accompanied by such offers. So this is something that is only useful to get upcoming games on their release day. In that sense, you can have a 12-month-subscription with a net loss of nothing, because you get the money you pay for the subscription completely back.
I'll stick to my no online, screw digital mantra. As most of you should know, another one of Nintendo's troll tactics is to grant 5% cashback on digital games, but only 1% cashback for physical games. But it's not hard to obtain physical copies at less than the MSRP on release day, so the cashback differential is commonly offset, making the decision to buy physical games very easy.