For those who've paid attention to Nintendo's paid DLC practices that started in 2012 with Fire Emblem's Awakening on the 3DS - the first Nintendo game to feature paid DLC - gamers were treated to a mixed bag, because Nintendo tried various approaches, including:
1. One individual level for a small price. (Fire Emblem series)
2. Multiple levels for a small price.(New Super Mario Bros. 2, Pikmin 3)
3. Options to buy individual DLC pieces in packs with a discount in comparison to purchasing everything individually.(Fire Emblem series)
4. Season passes that included everything. (Hyrule Warriors)
As a general rule, the less content that was in the DLC, the worse the price/value ratio was. Therefore the highest payments offered the best value.
The season pass approach (commonly called expansion pass by Nintendo) has become most prevalent on Switch. There's no good reason to believe that Nintendo acts generously, so it's much more likely that this change was driven by gamers voting with their wallets, i.e. they rather pay a high one-time fee for substantial content than getting small pieces for $/€2-3.
The Fire Emblem series was the most notorious with its garbage DLC, the only bright spot being the Fire Emblem Fates campaigns that went for the price of $/€20 for 25-30 hours of additional gameplay and story (so the same length as the initial campaign that was sold for $/€40). Today Nintendo announced that Fire Emblem: Three Houses will follow their other Switch games and have an expansion pass, this one being sold for $/€25.
This expansion pass includes everything that was split up into lots of pieces in the three 3DS Fire Emblem games and amounted to about $/€50 of DLC. You can expect the usual maps to farm gold, experience and items, additional quests, new costumes and a self-contained sidestory that spans several chapters (the above link doesn't specify this sidestory, but the eShop page of the game does). The rollout of the DLC will be similar to Xenoblade Chronicles 2, so the small stuff comes first while the sidestory will arrive last (scheduled to release before April 30th 2020).
Good job, Nintendo.