Weird comparison. With N64 everything was proprietary. The power brick, the memory card, the controllers. With Switch a lot more follows standards. USB-C charging. SD for storage. Bluetooth for controllers and headsets.

I don’t see a single reason to think Nintendo of that time would do anything differently.

The reason for not accepting whatever dock/adapter seems pretty good in this case. The dock should have active cooling to conform to user expectations. And there’s no signs that Nintendo will prevent anyone from making a dock that supports it as long as it follows the procedure to confirm that it has active cooling.