There is merit to Nintendo’s warnings
Just recently an engineer that goes by the Reddit username “VectorDriver” put up a fascinating breakdown of what is causing some Switch systems to brick. The bricking problem has been a thing for the past several years and is most famously blamed on using third party devices to charge or dock the Switch, and VectorDriver breaks it all down in a semi-dense electrical engineer tutorial of conductors, voltage, and Switch innards.
TLDR: when a publisher warns people not to use 3rd party devices they’re often protecting their own interests, but in this case, it has merit. The way the Switch consumes power is very particular according to this engineer (read: it has to do with PD, or “power delivery” charging), and when third party docks “cut corners,” they put the Switch at risk of a higher voltage rating than it can muster (some docks send 9V to the Switch when it can only take 6V).
But in a rare twist there’s actually another potential cause for bricked systems: bad type-C USB connectors. As VectorDriver points out, Nintendo’s USB-C connector is specifically designed for the Switch, allowing it to get as snug as possible in the dock. Third party dock connectors “want to emulate” this style according to VectorDriver, and do not follow any sort of certification process.
The entire writeup is worth a read if you’ve ever bricked your Switch or currently use a third party product. As VectorDriver puts it: you’re essentially playing Russian roulette, and there’s science to back it up.
An engineer’s POV on the 3rd party dock Switch bricking situation [Reddit]