You actually don't, and I have to give credit to nintendo for this one, there are only a few ways you can get banned (the main one being installing pirated games, the switch has telemetry that sends back data about the signatures of the games you have installed) but just running simple homebrew isn't one of them, you can load up custom firmware and run a game dumper without getting banned just fine. You can even play online with it active (I have done it).

The bigger problem is that only very old models of the console can be hacked without having to solder a modchip so this is completely inaccessible to most switch owners.