Looks like Nintendo has complied with the FTC's request to update the wording in their warranty. The new verbiage is already available, and Nintendo has provided a comment as well.

Nintendo statement
"Nintendo builds high quality products, while also striving to exceed expectations when supporting our customers. We continuously review and refine our support policies to ensure they embody that commitment. As part of that effort, we have updated our warranty text to clarify that Nintendo provides warranty service for defects not caused by the user or by other unauthorized acts. Revised warranty terms can be found at support.nintendo.com."
Nintendo's old warranty
"This warranty shall not apply if this product: (a) is used with products not sold or licensed by Nintendo (Including but not limited to, non-licensed game enhancement and copier devices, adapters, software, and power supplies."

Nintendo's new warranty
"This warranty shall not apply if this product has been damaged by products not sold or licensed by Nintendo (Including, but not limited to, adapters, software, and power supplies)."

QUELLE und TEXT: https://gonintendo.com/stories/308693-nintendo-updates-warranty-wording-following-warning-from-ftc

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