They were already breaking modded hardware with firmware updates and banning accounts. The previous EULA covered it, just less explicitly. Just sharing what I learned researching this last week. My personal preference would be for the Switch to be flashable with any OS.

They already did that with the 3DS onwards.

For example, if you had a flash card in your 3DS and a new firmware update detected it Nintendo would happily brick the 3DS:

https://www.digitaltrends.com/gaming/nintendo-3ds-can-be-rem...

They're probably bluffing to an extent, but just picture the dystopian scenario we're all heading towards: you're watching anything that's not {MegaCorporation or Government}-Approved Content™ on your TV and all of a sudden the screen goes dark and displays an ominous message, "This device has been permanently disabled due to non-approved usage. It will be retrieved by authorized personnel in the following days. Failing to comply will carry a serious fine. Thank you." Then you say "McDonald's! I'm lovin' it!" out loud so you can unlock your phone and proceed to complain on X before you're swatted by the police for doing so.

Sure, Nintendo definitely has the right to unilaterally and with no appeal or recourse, destroy a several hundred dollar device that you bought with your own money.

Nintendo claims the right to steal hundreds of dollars from you, permanently, with no notice or any hope of recovery.

Make sure to preorder switch 2!