What's the issue with replicating DAuth/AAuth servers?

[Ondrashek06]

I've asked the owners of a server revival project for the Switch whether it would be possible to also try to make alternate servers for DAuth and AAuth so you wouldn't have to place config files on your SD card, and they said that doing so would most likely get them shut down...

What's so special about DAuth and AAuth that a replica of these servers can't be made without Nintendo being furious about it?

 

[thesjaakspoiler]

Those settings can only be obtained from a Switch device in a way that Nintendo and their lawyers consider to be unlawful access with the objective to commit piracy or some other form of intellectual property violation.
The people from the revival project just don't want to deal with Nintendo in court because Nintendo usually brings in a big team of lawyers.